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Human cells have 23 pairs (46number) of chromosomes. The cell with longest life span in our body is Nerve Cells The average size of the cell is 3-30 microns (1 micron = 1/1000 mm). 1. Cell wall - found only in plant cells. It consists of non-living substances. eg: lignin, pectin, cellulose etc. 2. Cell membranes (plasmale- mma) It is the outer membrane of the cytoplasm found both in animals and plants. It is made of protein. In prokaryotes, there is no definite membrane bound nucleus Eg : Bacteria, Blue - green algae. In eukaryotes, there is a nucleus with definite double membrane. Plasma membranes are composed of phospholipids and protein. Cytosol - it is the soluble material in embryonic cell in which various organelles are embedded. 3. Endoplasmic Reticulum (ER) A network of tubes or channels of membrane in the cytoplasm which helps in protein synthesis and conduction of materials. BIOLOGY Father of Biology : Aristotle. Biology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy. The term ‘ Biology’ is coined by a French naturalist Jean Lamarck. Fundamental axioms of modern biology: 1. Cells are the basic unit of life 2. New species and inherited traits are the product of evolution 3. Genes are the basic unit of heredity 4. An organism will regulate its internal environment to maintain a stable and constant condition 5. Living organisms consume and transform energy. The CELL Cell is the smallest and fundamental unit of life. The smallest cell size is of a bacteria. The largest cell is of an ostrich egg. The largest human cell is the ovum. (.2mm) Nerve cell(neuron) is the longest cell. Aristotle ............................................. Father of Natures History/ Father of Biology Alexander Fleming ....................................... Father of Antibiotics Carolus Linnaeus .......................................... Father of Taxonomy Edward Jenner ........................................... Father of Immunology Louis Pasteur .......................................... Father of Microbiology Rudolph Virchow .......................................... Father of Pathology Robert Hook ................................................ Father of Sightology Robert Koch ............................................. Father of Bacteriology William Harvey .................................. Father of Blood Circulation W.M.Stanley ................................................... Father of Virology Ivan Pavlov ..................................... Father of Conditioned Reflex Ernst Von Baer .............................. Father of Modern Embryology Father of Important Branches Exampundit's Science Guidebook for SSC CGL, CHSL & Railways Exams www.exampundit.in

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Page 1: Science Guidebook for SSC CGL, CHSL ... - exampundit.in · Exampundit's Science Guidebook for SSC CGL, CHSL & Railways Exams . 4. Ribosomes: Externally small, dense, granular, spherical

Human cells have 23 pairs(46number) of chromosomes.

The cell with longest life spanin our body is Nerve Cells

The average size of the cell is3-30 microns (1 micron = 1/1000mm).

1. Cell wall - found only in plantcells. It consists of non-livingsubstances.eg: lignin, pectin, cellulose etc.

2. Cell membranes (plasmale-mma)It is the outer membrane of thecytoplasm found both inanimals and plants. It is madeof protein.

In prokaryotes, there is no

definite membrane boundnucleus Eg : Bacteria, Blue -green algae. In eukaryotes,there is a nucleus with definitedouble membrane.

Plasma membranes arecomposed of phospholipidsand protein.

Cytosol - it is the solublematerial in embryonic cell inwhich various organelles areembedded.

3. Endoplasmic Reticulum (ER)A network of tubes or channelsof membrane in the cytoplasmwhich helps in proteinsynthesis and conduction ofmaterials.

BIOLOGY Father of Biology : Aristotle. Biology is a natural science

concerned with the study oflife and living organisms,including their structure,function, growth, origin,evolution, distribution, andtaxonomy.

The term ‘ Biology’ is coinedby a French naturalist JeanLamarck.

Fundamental axioms of modernbiology:1. Cells are the basic unit of

life2. New species and inherited

traits are the product ofevolution

3. Genes are the basic unit ofheredity

4. An organism will regulateits internal environment tomaintain a stable andconstant condition

5. Living organisms consumeand transform energy.

The CELL Cell is the smallest and

fundamental unit of life. The smallest cell size is of a

bacteria. The largest cell is of an ostrich

egg. The largest human cell is the

ovum. (.2mm) Nerve cell(neuron) is the

longest cell.

Aristotle ............................................. Father of Natures History/ Father of BiologyAlexander Fleming ....................................... Father of AntibioticsCarolus Linnaeus .......................................... Father of TaxonomyEdward Jenner ........................................... Father of ImmunologyLouis Pasteur .......................................... Father of MicrobiologyRudolph Virchow .......................................... Father of PathologyRobert Hook ................................................ Father of SightologyRobert Koch ............................................. Father of BacteriologyWilliam Harvey .................................. Father of Blood CirculationW.M.Stanley ................................................... Father of VirologyIvan Pavlov ..................................... Father of Conditioned ReflexErnst Von Baer .............................. Father of Modern Embryology

Father of Important Branches

Exampundit's Science Guidebook for SSC CGL, CHSL & Railways Exams

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4. Ribosomes: Externally small,dense, granular, sphericalbodies found in free state inthe cytoplasm, composed ofRNA and proteins. They helpin synthesis of proteins.

Rough endoplasmic reticulumis the normal ‘ER’ withribosomes attached to it.

Nucleus contains nucleoli andnucleoli are the centres of thesynthesis of ribosomal RNA.

5. Golgi bodies: Bag likestructures formed ofmembranes. Their functionsinclude secretion of varioussubstances.

6. Vacuole: A fluid filled sacwithin a cell. The watery fluidenclosed in the vacuole iscalled ‘Cell Sap’. It is slightlyacidic or neutral. Osmo-regulation is the main function

7. Mitochondria: Rod like orspherical, semi solid structurescontaining DNA. Theysynthesise A.T.P (AdenosineTri phosphate)

Mitochondria is the powerhouse of the cell. It is also a

double- membrane boundorganelle. The inner membraneis thrown into folds calledcristae to increase the surfacearea.

8. Peroxisomes and glyoxysomesare known as microbodies.They are enzyme bags.

9. Lysosomes are known as“suicide bags”, as theycontain hydrolysing enzymes.Occasionally they digest thewhole cell or part of it.

10. Plastids: Small bodies foundin the cells of higher plants.They are of many types.

Chloroplasts : are the centresof photosynthetic activity. It isfound only in photosyntheticplant cell. Chloroplast is agreen plastid.

Chloroplasts have doublemembrane, lamellae orthylakoids which absorb solarenergy and pigments likechlorophylls and carotenoids.i) Leucoplasts: Colourless

starch storing particlesii) Chromoplasts: Are

coloured particles whichgive colour to fruits andflowers.

11. Nucleus: The nucleus controlsall cell activities and enclosethe nucleoplasm. Nucleus isresponsible for transfer ofheredity characteristics.

12. Centrosome: A rather densearea of protoplasm, lies closeto nucleus.

Plant cell is different fromanimal cell as it contains cellwall surrounding plasmamembrane and chloroplastsand devoid of centrioles whichis seen only in animal cells.

Adenosine Triphosphate(ATP) provides energy for allkinds of activities of a cell.

ATP is called the ‘universalbiological energy currency'.

ATP synthesis takes place inmitochondrion.

Energy is stored in the mito-chondria as ATP molecules.

The physical basis of life is'protoplasm'.

Chromosome is made up ofDNA & Proteins.

Chromosomes, other than thesex chromosomes, are calledautosomes.

The ribosomes are chieflyconcerned with the synthesisof protein.

Types of cells Prokaryotes: Prokaryotes lack

a nucleus (though they dohave circular DNA) and othermembrane-bound organelles(though they do containribosomes). Bacteria andArchaea are two domains ofprokaryotes.

Eukaryotes: Eukaryotes, onthe other hand, have distinctnuclei bound by a nuclear

DNA & RNA DNA (Deoxyribonucleic Acid )and RNA (Ribonucleic Acid) are

two different nucleic acids found in the cells of every living organ-ism. Both have significant roles to play in cell biology.

DNA is found mainly in the nucleus of the cell, while RNA is foundmainly in the cytoplasm of the cell.

DNA contains the genetic codes to make RNA and the RNA in turnthen contains the codes for the primary sequence of amino acidsto make proteins.

Within the cell structure, DNA is organized into structures calledchromosomes, which are duplicated during cell division. Thesechromosomes would then release the genetic codes that will betranscribed and carried by the RNA to the ribosome. The ribosomewill then synthesize new proteins that will help the body grow.

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membrane and membrane-bound organelles (mitochondria, chloroplasts, lysosomes,rough and smooth endoplasmic reticulum, vacuoles). Inaddition, they possessorganized chromosomeswhich store genetic material.

Cell Division Cell division is the process by

which a parent cell divides intotwo or more daughter cells. Celldivision is usually a smallsegment of a larger cell cycle.

Cell cycle is composed of threephases- interphase, mitosis,cytokinesis.

Mitosis means the division ofnucleus and cytokinesismeans the cytoplasmicdivision.

Two kinds of Cell Division :Mitosis and Meiosis.

Mitosis occur in body cells,results in formation of twodaughter cells with equalnumber of chromosomes.

Meiosis Occurs in reproductive cells. It causes areduction in number ofchromosomes in the cell.

Micro Organisms The study of microorganisms

is called microbiology. Anton van Leeuwenhoek's

discovered microorganisms in1675, using a microscope of hisown design.

Microorganisms are verydiverse; they include bacteria,fungi, archaea, and protists;microscopic plants (greenalgae); and animals such asplankton and the planarian.

Diseases caused by BacteriaLeprosy, Tetanus, Whooping Cough, Typhoid Fever, ParatyphoidFever, Cholera, Plague, Tuberculosis, Meningitis, BacterialPneumonia, Diarrhoea, Diphtheria, Bacterial dysentry, Anthrax,Syphilis and Gonorrhoea.

Microorganisms live in all partsof the biosphere where thereis liquid water, including soil,hot springs, on the ocean floor,high in the atmosphere anddeep inside rocks within theEarth's crust.

Bacteria were first observed byAntonie van Leeuwenhoek in1676.

The name bacterium wasintroduced much later, byChristian Gottfried Ehrenbergin 1838.

Bacteria are microscopicunicellular prokaryoticorganism and lack of membranebound nucleus and organelles.

Bacteria are eventually placedin a Kingdom Monera.

Reproduction in bacteria islargely asexual by binaryfission.

Respiration of bacteria areaerobic and anaerobic.

Bacteria display a widediversity of shapes and sizes,called morphologies.

Bacteriophages are viruseseating (destroying) bacteriaand were invented byd’Herelle.

Bacteriology is the study ofbacteria.

‘Virus’ the term is coined byM.W. Beigerinck, a Dutchmicrobiologist.

Fungal Diseasesin Human

RingwormTineaAthelete’s footMadura footDhobie itch

A virus is a small infectiousagent that can replicate onlyinside the living cells oforganisms.

All viruses are nucleoproteinparticles and contain eitherDNA or RNA. The geneticmaterial inside the viruses isprotected by a protein coatcalled ‘capsid’.

Viruses lack the cellularorganisation of the livingorganism, but make use of thecellular machinery of the hostcell to multiply themselves.

A complete viral particlecapable of infection is called a‘virion’.

‘Viroids’ are newly foundgroup of pathogenic agents,much smaller than the viruses.

The study of viruses is knownas virology, a sub-speciality ofmicrobiology.

The study of viruses is knownas virology, a sub-speciality ofmicrobiology.

L.S.D. (Lysergic acid diethy-

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KingdomClassification

Five kingdom classification wasdeveloped by R.H.Whittaker.

The five kingdoms are Monera,Protista, Fungi, Plants andAnimals.

Kingdom Monera Monera includes prokaryotic

cells. Eg : True bacteria, Fun-gus-like bacteria i.e. ‘Autono-my cetales’, Blue - green algae(cyanobacteriae).

Antibiotic drugs like strepto-mycin, erythromycin etc. areobtained from actinomycetes isKingdom Monera.

Kingdom Protista They are unicellular or colonial

eukaryotes. Reproduction isboth sexual and asexual.Motility is by Flagella, havediverse nutritional habits. Eg :Euglena, Dinoflagellates,diatoms etc.

Kingdom Fungi Multi nucleate, non-

photosynthetic, non- motileorganisms. Reproduction is byboth asexual and sexual means.

Two divisions - myxomyco

phyta (slime molds) andEumycophyta (True fungi)

The true fungi is characterisedby a definite cellular bodycomposed of filaments calledmycelium. The individualmycelium filaments is calledhyphae.

Water moulds, bread moulds,club fungi are examples.

Ascospores or basidiosporesare the products of sexualreproduction in Fungi.

The Plant Kingdom Plants are the primary

producers in nature. Flora is the plants of a particular

region and Fauna is the animalsof a particular region. Flora andFauna together constitute theplants and animals of a region.

The part of the earth and itsatmosphere that is capable ofsupporting living things is thebiosphere.

Biosphere is divided intoLithosphere, Hydrosphere,Atmosphere etc.

Nitrogen Fixation meansconversion of atmosphericnitrogen into usefulcompounds like nitrates withthe help of bacteria and fungi.

The biological nitrogenfixation is done by nitrogenfixing bacteria such asRhizobium Nostoc andAzetobactor.

Plants absorb the elementnitrogen in the form of nitrates.

Cyanobacteria is a blue greenalgae.

The profuse amount of pollengrains liberated by pine forestsat the time of pollination duringthe months of March-April isreferred to as ‘SulphurShowers.’’

Araucaria embricate, agymnosperm plant is commonlyknown as ‘Monkey’s Puzzle’

Litmus is obtained from alichen.

Lichen is an association offungus and algae.

Turmeric is obtained from thestem of plant.

Cloves are dried flower budsof plant syzygium aromaticum.

Potato is a tuber crop. The native place of potato is

America

Photosynthesis is vital for

all aerobic life on Earth. Pho-

tosynthesis is a process that

converts carbon dioxide into

organic compounds, espe-

cially sugars, using the energy

from sunlight. Photosynthesis

occurs in plants, algae, and

many species of bacteria. Pho-

tosynthesis uses carbon diox-

ide and water, releasing oxy-

gen as a waste product.

Smallest seeds Orchid seedsLargest leaf Victoria regiaIndia's national flower LotusLargest flower RafflesiaSmallest flower WolffiaOldest living plant of the worldPinusStudy of trees- dentrologyLargest trees in plant world -Conifers

King of fruits - MangoPoorman’s orange - TomatoPoorman's wood - bamboo

lamide) is obtained from afungi, called Ergot.

Smallest Cell - Pleuro Pneumo-nia Like Organism (PPLO). Itis a mycoplasma.

HIV is an RNA virus. Smallest living thing - Virus

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Vanilla, a flavouring material, isextracted from the fruit of anorchid ‘Vanilla Planlifolia.’

Rubber is obtained from thelatex of Hevea brasiliensis.

The milky juice that oozes fromsome trees like rubber is knownas latex.

Cotton, jute, silk, wool, etc arenatural fibres and nylon isartificial fibre.

Sugarcane is a type of grass. The fruit sugar is fructose. Tissue culture is the method of

producing plants from minuteplant fragments.

The wall of the plant cell ismade of cellulose.The cellu-lose cannot be digested byhuman alimentary canal.

The largest flower in the worldis Rafflesia and the smallest

one is Wolffia (duck weed). The largest sperms among

plants are found in gymno-sperms.

In plants gaseous exchangeoccur through stomata.

The roots which do not growfrom a main root (radicle) butdirectly from the stem are calledadventitious roots.

DNA (Deoxyribo Nucleic Acid)and RNA (Ribo Nucleic Acid)are the two kinds of nucleicacids.

In a plant cell, DNA is found inchloroplast, mitochondria andnucleus.

Nepenthes, sundew, drosera,etc. are some of theinsectivorous plants.

Insectivorous plants obtainnitrogen from animal bodies.

Organisms which obtain theirfood from non living material

in their environment are calledsaprophytes

Classification of Plant Kingdom1. Rhodophyta (Red algae): Are

mostly multicellular marineplants. Their reddish colour isdue to a pigment, phycoerythrin.

2. Phaeophyta (Brown Algae):Are multicellular marine plantsgrowing on rocks or attachedto sea shores. Their brownishcolour is due to xanthophyllpigment called fucoxanthin.

3. Chlorophyta (Green Algae):Are a group of bright greenaquatic, unicellular plants.

4. Bryophyta: Simple, nonvascular small plants grow inmoist places. Thallus like plantbody is attached to the soil byrhizoids.eg: Liver worts, horn worts,mosses, etc.

5. Lycopodophyta (clubmosses): Multicellularterrestrial plants with vasculartissues.

6. Arthrophyta (Horsetails): Aremulticellular plants withvascular tissues. Arthrophytaare largely an extinct grouprepresented by a single livinggenus, the Equisetum.

7. Pterophyta (Ferns): Aremulticellular plants withvascular tissues; Here seedsare not produced.

Gymnosperm8. Cycadophyta: Are multicellular

terrestrial plants with vasculartissues. The stem is large andwoody, leaves are large andfern like.eg: cycas, zamia (sago tree),etc.

Subdisciplines of botany

Agronomy: Application of plant science to crop production

Bryology: Mosses, liverworts, and hornworts

Economic botany: Study of plants of economic use or value

Ethnobotany: Relationship between humans and plants

Forestry: Forest management and related studies

Horticulture: Cultivated plants

Lichenology: The study of lichens

Paleobotany: Fossil plants

Palynology: Pollen and spores

Phycology: AlgaePhytochemistry: Plant secondary chemistry and chemical

processesPhytopathology: Plant diseases

Plant anatomy: Cell and tissue structure

Plant ecology: Role of plants in the environment

Plant genetics: Genetic inheritance in plants

Plant morphology: Structure and life cycles

Plant physiology: Life functions of plants

Plant systematics: Classification and naming of plants

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9. Conifers: Are multicellularplants with well developedtissues. Leaves are simple,smaller and needle like.eg: Cedrus (deodar), Taxus(Yew), Pine

10. Angiosperms: More advancedflowering plants with welldeveloped vascular tissues.They make up more than halfof all known species of plants.

Flowering plants are dividedinto two classes – Dicotyledons (Dicots), Monocotyledons (monocots).

Other Classifications Terrestrial: Plants which

grow in soil. Hydrophytes: grow in water. Epiphytes: which perch on

other plants but do not takenourishment from them.

Xerophytes: Are adapted togrow in a dry habitat likedeserts and can survivewithout moisture.eg: cacti

Mesophytes: thrive undercondition intermediate between very wet and very dry.The great variety of cropssuch as beans, tomatoes, pear,etc. belong to this category.

Parasitic: which depend onother plants for theirnourishment. They lackchlorophyll and thus cannotmake their own food.eg: bacteria, fungi.

Carnivorous plants: plantswhich trap insects and othersmall creatures on their stickyleaves.

Plant Nutrition Plant nutrition is the study of

the chemical elements that are

necessary for growth. There are 17 essential plant

nutrients. Carbon and oxygenare absorbed from the air, whileother nutrients including waterare obtained from the soil.

Macro Nutrients Carbon: Carbon forms the

backbone of many plantsbiomolecules, includingstarches and cellulose. Carbonis fixed through photo-synthesis from the carbondioxide in the air and is a partof the carbohydrates that storeenergy in the plant.

Hydrogen: Hydrogen also isnecessary for building sugarsand building the plant. It isobtained almost entirely fromwater.

Oxygen: Oxygen is necessaryfor cellular respiration. Cellularrespiration is the process ofgenerating energy-rich adeno-

sine triphosphate (ATP). Phosphorous is important in

plant bioenergetics. Potassium regulates the

opening and closing of thestomata by a potassium ionpump.

Nitrogen is an essentialcomponent of all proteins.

Sulphur is a structuralcomponent of some aminoacids and vitamins, and isessential in the manufacturingof chloroplasts.

Calcium regulates transport ofother nutrients into the plantand is also involved in theactivation of certain plantenzymes. Calcium deficiencyresults in stunting.

Magnesium is an importantpart of chlorophyll, a criticalplant pigment important inphotosynthesis.

Micro nutrients Iron is necessary for

photosynthesis and is presentas an enzyme cofactor inplants. Iron deficiency canresult in interveinal chlorosisand necrosis.

Molybdenum is a cofactor toenzymes important in buildingamino acids.

Copper is important forphotosynthesis.

Manganese is necessary forbuilding the chloroplasts.

Zinc is required in a largenumber of enzymes and playsan essential role in DNAtranscription.

In higher plants, Nickel isessential for activation of

CultivationsSericulture is rearing of silkworms.Horticulture is the cultivation offlowers, fruits and ornamentalplants.Pisciculture is the art of rearingfishes.Silviculture is forest planting.Apiculture means honey making.Viticulture is grape cultivation.Vermiculture is breeding ofworms useful to farmers.Floriculture is cultivation offlowering plants.Arboriculture means cultivationof tree and vegetables.

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urease, an enzyme involvedwith nitrogen metabolism thatis required to process urea.

Chlorine is necessary forosmosis and ionic balance; italso plays a role in photo-synthesis.

Tissues1. Parenchyma : thin - walled,

polyhedral cells with livingprotoplasm, metabolically mostactive.

2. Collenchyma : Cell wall is madeup of thin and thick portionswith thickening in the corners.Found below the epidermis(stem skin).

3. Sclerenchyma: highlythickened cell walls. So it is theprimary strengthening tissuefound in mature plants. Noliving protoplasm, some ofthese are highly elongatedcalled fibres.

Complex Tissues Xylem - primarily a conducting

tissue meant for transport ofwater and mineral elements.Highly thickened walls.

Phloem - meant for thetransport of food material fromthe leaves where it issynthesized to the storage orconsumption organs.

Epidermis - outermost layer ofthe plant body and is primarilyprotective in nature.

Secretory Tissues : Examplesof secretions are resin,mucilage, essential oils, gums,nectar, etc.

Morphology of the PlantRoot:Root develops from the‘radicle; forming tap root system or

from the base of the stem formingthe fibrous root system.Stem: Stem and leaves constitutethe shoot system.

Plant Movements Two types of movements are

noted in plants.1.Growth movements(irreversible) (2) Turgormovements (reversible).

Plants exhibits movements inresponse to external stimuluslike touchings, light,gravitation, water etc.

Chemical stimulus inducedgrowth is called chemotro-pism.

Bending of stem towards lightis due to phototropism.

Phototropism means move-ments ofPplan ts towardslight.

The movement of plant or-gans in response to the forceof gravity is called as geotro-pism.

The movement of an organinduced by contact with a for-eign body is calledhaptotropism.

Water stimulus inducedgrowth movements are calledhydrotropism.

The curvature movementsof plant parts in response tothe stimulus of contact aretermed as thigmotropism.

Growth movements in re-sponse to the stimulus of heator cold is called thermotro-pism.

Alternation of day and nightcauses movements of plantscalled nyctinastic movements.

Seismonastic movements are

in response to a touch orshock stimulus.

Living medium of plants Habitat: The normal locality

inhabited by a plant or animal,particularly in relation to theeffect of its environmentalfactors.

World habitat day - IstMonday of October.

The vegetation of deserts iscalled xerophytes. eg: Opuntia.

A hydrophyte is an aquaticplant.

Plants which grow in salinewater are called Halophytes.

Plants growing well in fullsunlight are called Helio-phytes.

Plants which grow luxuriantlyin rainy season and shed allleaves in summer are calledTropophytes.

Oxylophytes : plants growingon acidic soil.

Lithophytes: plants growingon rocks.

Plants growing in marsh arecalled Helophytes.

Hydroponics: is a method ofcultivating plants withoutusing soil but by using nutrientsolution.

Growth Regulators ofPlants Certain chemical substances

regulate the growth and dif-ferentiation of plants. Thesesubstances are called plantgrowth regulators or phytohormones.

The auxins induce cell elon-gation and root initiation.

Indol - 3 Acetic Acid (IAA) isan important Auxin.

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Stem elongation and dor-mancy breaking are inducedby gibberillins.

Dormancy is the period inwhich seeds remains inactive.

The hormone which helps inflowering of plants - florigen.

Cytokinins help to induce celldivision and cell elongation.(Cytokinins are largelypresent in coconut water.)

The plant hormone that con-trols fruit ripening is ethylene.

Unripe fruits can be made toripe before proper time if theyare kept in ethylene atmo-sphere.

Abscisic acid cures ageingand abscission of leaves.

It inhibits germination ofseeds.

Seed dormancy is due to ab-scisic acid.

Plant Processes PHOTOSYNTHESIS is the

process by which greenplants manufacture food inthe form of carbohydrates byusing water, CO

2 and sunlight.

During Photosynthesis plantsuse carbon dioxide and giveout oxygen.

Oxygen balance in the atmo-sphere is maintained throughthe process of Photosynthe-sis.

The percentage of light en-ergy fixed in photosynthesisis generally around 1%

Photosynthesis takes placefaster in red light

Plant pigments do not absorball the wavelengths of visiblelight. Out of the seven colours

of light, only blue, red andsome violet light are absorbed.

During day time plants takein carbondioxide and give outoxygen.

GUTTATION: In some plants,water oozes through certainpores in the form of liquid, thatpores remain permanently openand this phenomenon is calledguttation.

OSMOSIS :The process bywhich water diffuses througha semi-permeable membranefrom a region of higher concen-tration of a solution to a regionof lower concentration of a so-lution.

TRANSPIRATION: Theleaves excretes water throughstomata by transpiration pro-cess.

The required ingredient forphotosynthesis in plant is Allthe above

For the process of respirationin plants oxygen is necessary

Xylem is responsible for theconduction of water in plantsPlants get water through theroots because of capillarity

Phloem carries prepared foodfrom leaves to all parts ofplant.

Seed Dispersal andPollination

Pollination means transfer ofpollen grains from the antherto the stigma of the same plantor a different plant.

Pollination by water -Hydrophily

Pollination by Bat -Chiropterophily

Pollination between two flow-ers of one plant gytanogamy

Pollination by insects is calledEntomophily.

Pollination by birds is calledOrnithophily.

Pollination by animals is calledZoophily.

Pollination by wind is calledAnemophily.

The pollen grains in theplants are produced in anther.

The chief pollinators of ouragrihorticulture crops arebees.

Wind borne pollen grainscause pollen allergy.

In plants like castor andmoringa seed dispersal takesplace through wind.

In Vallisnaria pollinationoccurs by water.

Seed dispersal in coconutoccurs through water.

The Kingdom ofAnimals

The animal with the longestlife span on the land is el-ephant, while the animal hav-ing the longest life span, ingeneral, is turtles and tor-toises.

Blue Whale is the biggest andthe heaviest mammal.

The smallest ape is Gibbon. Chimpanzee is the most intel-

ligent ape. Elephant tusks are enlarged

incisors. Fishes respire through gills. The vertebrate which has a two

chambered heart is fish.

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Coprophytes are the animalswhich derives their food fromfaecal matters.

The organism which has themaximum number of ribs is thesnake. The largest snake isthe anaconda found in theAmazon region in SouthAmerica.

Kangaroo is a nocturnal her-bivore.

Zebras are jockingly called''the ponies in pygamas.''

The main chemical content ofegg shell is calcium carbo-nate.

Hibernation is the period oflong sleep for animals in coldweather when there is no foodavailable. During this periodanimals go underground andtheir metabolic activity be-comes very low and hencethey do not need to eat ordrink during this period.

The animal found in theadvertisement board of forestdepartment with the heading“I have no medicinal value” isblack ape.

Sanguivores are the animals

feeding on blood. Frugivoresare the animals feeding onfruits.

The Kangaroo rat never drinkswater in its entire life.-

Ostrich, Rhea, Kiwi and Pen-guin-all are flightless birds.

Dodo (a flightless pigeon)which appeared in Mauritiusis now extinct.

The smallest flightless bird iskiwi, while the smallest flyingbird is the Bee humming birdof Cuba.

Growth of tadpole into a frog

The Classification of animalsAnimal Kingdom can be split up into main groups, vertebrates

(with a backbone) and invertebrates (without a backbone). around800,000 species have been identified in the Animal Kingdom —most of them in the Arthropod phylum.

Scientists classify each organism according to its: Kingdom,Phylum, Class, Order, Family, Genus and Species.

The science of classifying organisms is called taxonomy.Biologists classify living things into two kingdoms, the PlantKingdom and the Animal Kingdom.

is called metamorphosis Cobra venom affects the ner-

vous system and viper venomthe blood circulatory system.

A baby cockroach is callednymph.

Organism is called the ‘slip-per animal cule’ paramecium

The organism which performs

Largest ape ............................................................. GorillaTallest animal .......................................................... GiraffeLargest reptile .................................................... CrocodileLowest recorded temperature for a humanbeing to survive ..................................................... 20.30

CFastest Animal ......................... Cheetah (speed 60-63 km/hr)Smallest bird ................................................ Humming birdLargest bird ...................................... North African OstrichLongest poisonous snake ................................ King CobraLargest mammal (animal) ............. Blue Whale (wt. 209 tones)Largest land animal ................. African Elephant (wt. 7 tones)Largest teeth ........................ Elephant tusks (upper incisors)

The animal classes that arevertebrates include

Jawless fish Armored fish Cartilaginous fish Bony fish Amphibians Reptiles Birds Mammals

Invertebrates include Sponges Jellyfish, hydras,

sea anemones, corals Comb jellies Flatworms Molluscs Arthropods Segmented worms Echinoderms

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Physiology and HealthI. Carbohydrates

Organic compounds contai-ning carbon, hydrogen andoxygen which constitutesugars (Starch, cellulose,glucose etc) and supplycalories for body activity.

The general formula ofcarbohydrate molecule isCn (H2O)n.

The sources of carbohydratesare rice, wheat, honey, sugar,potato, carrot. Deficiency ofcarbohydrates causes weightloss and weakness.

Polyhydroxy aldehyde orketones are carbohydrates.

Based on the number of sugarunits they can be classifiedinto, Monosaccharides, Oligo-saccharides and Polysaccha-rides.

II. ProteinsProteins are highly complexnitrogenous compound foundin all living organisms. Proteinsare hydrolysed in the body toproduce amino acids and areessential for growth and repairof the body tissues. They alsoprovide energy when caloriesare deficient.Sources: Milk, fish, meat, eggs,nuts, dal.

Soyabean seeds possesshighest percentage of proteins(30-35%).

Prolonged protein deficiencycause severe undernourishment - a seriouscondition Kwashiorker isresulted mostly in children.

III. FatsFats are insolube in water butsoluble in fat solvents. Major

sources are - butter, ghee, oils,ground nuts, almonds, etc.

One gram of fat yields 9.3calories of energy.

IV. VitaminsVitamin A, D, E, K are fatsoluble whereas vitamin Bcomplex and C are watersoluble.

Rich sources of vitamin A areleafy vegetables, animal fat,carrot, spinach, milk etc.

Severe deficiency of Vitamin Aresults in Xerophthalmia andNightblindness.

Rich sources of vitamin B arecereals, eggs, fruits, liver,pulses.

Vitamin C is found in oranges,lemon, vegetables and milk.

Milk, egg, liver etc are richsources of vitamin E.

Vitamin E is considered bothas a vitamin and hormone.

The source of vitamin K isgreen leafy vegetables andfishes, pea etc.

Vitamin K is essential for bloodcoagulation.

If milk is exposed to sunlightfor a long time, vitamin B2 willbe lost.

Excessive intake of polishedrice causes deficiency of B1(Thiamine).

Cow milk is a rich source ofvitamin A.

Vitamin D, can also besynthesised in our body withthe help of sun light.

Shark liver oil and cod liver oilare rich sources of vitamin D.

Vitamin B12 (Cyanocobalamine)is a cobalt containing vitamin.

Even though the amounts ofvitamins required are smallcompared to other nutrients, it

Six Basic AnimalGroups

Amphibians (Class Amphibia)are one of the six basic groupsof animals.

Amphibians include frogs,toads, caecilians, newts andsalamanders.

Birds (Class Aves). Birds, bestknown for their ability to fly,are unmatched in their com-mand of the skies.

Invertebrates are one of the sixbasic groups of animals. Katy-dids, spiders, sea squirts, oc-topuses, earthworms, starfish,beetles, hydras, dragonflies,sponges, corals, snails, andjellyfish are a handful of theinvertebrates alive today.

Fish are cold-blooded, aquaticanimals that have scales, gillsand fins.

Mammals (Class Mammalia)are one of the six basic groupsof animals.

Reptiles (Class Reptilia) arecold-blooded vertebrates thatdiverged from ancestral am-phibians about 340 millionyears ago.

the sex transformation incrabs - Sacculina.

The population of reptiles ismaximum on earth.

Saurology is the study oflizards.

Ants go in a line by thesecretion of trail pheromones.

The tallest living bird isOstrich.

Silver fish is not a fish but awingless insect.

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Vitamin

Retinal :(Vitamin A) (Fat soluble)

T h i a m i n e(Vitamin B) (Water soluble)

Ribofla win(Vitamin B) (Water soluble)

Niacin(Water soluble)

Pyridoxine(Vitamin B6) (Water soluble)

Folic Acid (Water soluble)

Cyanocobalamine(Vitamin B12) (Water soluble)

Ascorbic acid(Vitamin C) (Water soluble)

Calciferol(Vitamin D) (Fat soluble)

Tocopherol(Vitamin E) (Fat soluble)

Phyl loquinones(Vitamin K) (Fat soluble)

Best Food Source

Carrots, yellow and green veg-etables. Other sources includebutter, milk, fish-liver oil.

Whole grains, yeast, liver, egg,pork, nuts.

Cereals, legumes, milk, egg,liver, kidney, yeast.

Lean meat, liver, milk, eggs,nuts, whole grains.

Salmon, yeast, yogurt, corn,spinach, cheese, cereals & le-gumes. Also synthesised by in-testinal bacteria.

Yeast, liver, green leafy veg-etables. Synthesized by intesti-nal bacterial also.

Liver, kidney, meat, eggs, milkand cheese. (Note:Absent in vegetables, only vi-tamin containing cobalt.)

Citrus fruits, tomatoes, cabbage.

Fish liver oils, egg yolk, milk,butter. Also synthesized in thehuman body by the skin underthe influence of sunlight.

Wheat germ, fresh nuts, seedoils, green leafy vegetables.

Liver, spinach, cauliflower,green tomatoes.

Function

Synthesis of the visual purple ofthe retinal rods.Maintains general health ancvigour of epithelial cells. Henceessential for good skin and hair.

Carbohydrate metabolism. En-sures normal functioning of thecentral nervous system.

Essential carbohydrate and pro-tein metabolism especially in thecells of the eye, skin, intestines,and blood.

Inhibits production of choles-terol and helps in the breakdownof fats, proteins and carbohy-drates.

Essential for amino-acid metabo-lism. Assists production of anti-bodies.

Helps normal production ofblood cells. Identified in chro-mosomes an important repro-ductive factor.

Necessary for red blood cells for-mation and normal functioningof nervous system.

Influences permeability of cap-illary walls. Develops immunityagainst diseases. Forms collagen.

Controls calcium and phospho-rus metabolism which contributeto formation of teeth and bones.

As anti-oxidant which protectslipids of cells membranes againstoxygen damage.

Assists in the production of pro-thrombin and other factors thatensure normal clotting of blood.

Deficiency disease

Xerophthalmia: drying ofcornea and ulceration. Nightblindness: Inability to see inthe dark. Keratinization ofepithelium: Dry skin and hair.

Beri-beri: Partial paralysis ofskeletal muscles and digestivedisturbances.

Characterised by corneal ulcer-ation and cracking of skin (es-pecially around the lips).

Pellagra: Characterised bydermatitis (skin inflammation),diarrhoea and dementia (loss ofintellectual function).

Epileptiform seizures observedin children. Symptoms includedermatitis of eyes, nose andmouth; retarded growth.

Macrocytic anaemia: Produc-tion of abnormally large redblood cells.

1. Pernicious anaemia.2. Neuro-psychiatric abnor-malities: Memory loss, moodand personality changes.

Scurvy: Swollen gums, teethloss, bleeding gums.

Rickets (in infants) Bones be-come soft (deformed).Oesteomalacia (demineral-ization of bones)

Deficiency not reported in hu-mans Causes sterility in rats.

Haemorrhage: Subcutaneousand intramuscular bleedings dueto delayed clotting time.

Source and Role of Principal Vitamins

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is very necessary. Otherwiseseveral deficiency diseases arecaused in the body.

The name ‘vitamin’ is coinedby J.Funk (1912)

Milk is a rich source of allvitamins except vitaminC.

Vitamin D(in skin) and vitaminK (in liver) can be synthesizedby our body.

Deficiency of protein ,carbohydrates and fats resultsin protein - energy -malnutrition.

Protein deficiency causesKwashiorkor- skin cracks andbecome scaly, abdomen swells,hair become reddish .

Marasmus child show allabove symptoms besideswasting of muscles.

Diseases restricted to givenregion and arising from itsspecific environment conditionare called endemic diseases. Eg: Goiter in sub - Himalayanregion.

Pellagra is common amongstpeople living on a maize diet,because maize interferes withthe absorption of niacin inbody.

Overdose of water solublevitamin does not cause anyharm but accumulation of fatsoluble vitamin can be toxic. Itcan lead to hypervitaminosis.

Vitamin A accumulate in liverwhile vitamin D promotes highCa+ absorption which damagethe kidney where it isdeposited.

Vitamin A Deficiency causesNight Blindness andKeratomalacia.

Deficiency of Vitamin B1(Thiamine) causes Beri Beri.

Vitamin B3 (Niacin) deficiencycauses Pellagra.

Vitamin B6 Deficiency- Anemia. Vitamin B5 deficiency -

Paresthesia Vitamin C deficiency - Scurvy Vitamin D deficiency - Rickets

Modes of Nutrition Autotrophic : Ability of

organism to prepare its ownfood.

Holophytic : Characteristic ofplants where by they preparecomplex food substancesusing simple raw materials.

Heterotrophic : Organism isunable to prepare its own food.

Holozoic : Mode of nutritioncharacteristic of animalswhereby simple substancesare obtained from complex foodsubstances.

Saprophytic : Absorbsnourishment from dead ordecaying organic matter.

Parasitic : Derives nutritionfrom living host withouthelping it in any way.

Homodont dendition :Consists of only one type ofteeth. They are used only forcatching prey, as homodontdoes not chew their food. Eg :Snakes.

Heterodont dendition : Morethan one type of teeth,differing in function, shapeand function. Eg : Human

Human BodyDigestive System The process of converting

food into energy giving sub-stances is carried out by thedigestive system.

The digestive system consistsof the alimentary canal (buccalcavity, oesophagus, stomach,small intestine, large intestineending in the rectum and anus)and the associated glands.

Alimentary canal is a long tubewhich is 6-9 metres long andstarts from mouth and ends atanus.

The parts of the alimentarycanal are Mouth , Pharynx,Oesophagus, Stomach, Smallintestine, Large intestine.

The mouth leads into a funnelshaped pharynx, which is the

Food SourceVitamin A (Retinol) Cod liver oil, carrotsVitamin B1 (Thiamine) Rice branVitamin C (Ascorbic acid) Citrus, most fresh foodsVitamin D (Calciferol) Cod liver oilVitamin B2 (Riboflavin) Meat, eggsVitamin E (Tocopherol) Wheat germ oil, unrefined veg.oilsVitamin B12 (Cobalamins) Liver, eggs, animal productsVitamin K (Phylloquinone/phytol naphthoquinone) Leafy green vegetablesVitamin B5 (Pantothenic acid) Meats, whole grains, in many foodsVitamin B7 (Biotin) Meats, dairy products, eggsVitamin B6 (Pyridoxine) Meat, dairy products.Vitamin B3 (Niacin) Meat, eggs, grainsVitamin B9 (Folic acid) Leafy green vegetables

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common passage for food andair.

Pharynx lead into oesophaguswhich is about 25cm long.

The three divisions of largeintestine are Caecum, Colonand Rectum.

Small intestine. It is the largestand narrow tubular part ofalimentary canal. It measuresabout 6 meters in length.

Small intestine, the highlycoiled portion has 3 divisionssuch as duodenum, jejunumand ileum.

Digestion is of two types Intra cellular digestion : The

digested products pass to thecytoplasm across theendocytotic inside membrane.Eg : Amoeba

Extra Cellular Digestion : Cellsynthesizes one or moreenzymes for digesting specifictype of nutrient.

The liver is the largest glandof the body. It secretes bile,containing bile pigments andbile organic salt. If intestinecontains no food, the bile flowsto gall bladder, instead ofduodenum ; which contract

and secrete bile later whenfood is present in intestine.

The large intestine secretes noenzyme and play only a minorrole in the absorption ofnutrients.

Lungs

The lung is the essentialrespiration organ in all air-breathing animals.

Lungs are the respiratoryorgan in higher vertebrates(man).

The main function of the lungsis the oxygenation of bloodand to supply oxygen to it.

The right lung is larger than theleft lung.

Right weight about - 620 g Left weight about - 570 g Alveoli are small air sacs of

the lungs through the walls ofwhich gaseous exchangetakes place between bloodand air.

The organ without muscle islungs

Pleura protects lungs fromharm.

The CO2 content in the air that

we exhale is about 8%.

The exchange of O2 and CO2takes place in lungs at alveoli.

The amount of air moving inand out of lungs during eachbreath is called tidal volume.

The maximum volume of airthat can be moved in or out ofthe lungs is referred to as thevital capacity of the lungs.

Eupnea –– Normal breathing Dyspnea –painful breathing Anexia – No O2 in inspired air Pneumonia, pleurosis, bron-

chitis, silicosis and emphy-sema are diseases affectingrespiratory tract.

SARS (Severe Acute Respi-ratory Syndrome) a lung dis-ease, is caused by Corona Vi-rus.

High altitude problems1. Asphyxia - Oxygen starvation

due to low atmospheric oxygenis called asphyxia.

2. Hypoxia - refers to a generallow level of oxygenavailability. Physiologically itrefers to a deficiency of oxygenat the tissue level.

Tobacco smoke and exhaustfumes result in carbonmonoxide poisoning.

The binding capacity ofcarbon monoxide is 200 timesthan that of carbondioxide withhaemoglobin.

A leaf like cartilagenous flap,the epiglottis guards theopening of glottis.

Sleeping in a closed room witha burning kerosene lamp maylead to death due to lack of O2.

In mammals, the body cavityis partitioned into thoracic andabdominal parts by diaphragm.

Stom

ach

Liver

GallBladder

LargeIntestine

SmallIntestine

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Heart

The cardiovascular systemcomprises the heart, veins,arteries and capillaries.

Heart is the pumping organ ofblood vascular system.

Heart length - 12 cm Heart width - 9 cm The normal heart beat is 70-

72 per minute in males and78-82 per minute in females.

The heart beat of a child ismore than that of an adult. ie140/min

The circulation of blood in thebody is regulated by the heart.

The human heart is on the leftside beneath the left nipple.

The pericardium protectsheart from harm.

The average weight of theheart is about 340 gm in menand 225 gm in women.

The human heart has fourchambers, a pair of auriclesand a pair of ventricles.

The human heart consists offour chambers and in fish theheart consists of two cham-bers. In those of amphibiansthere are 3 chambers. Heart ofreptiles is incompletely di-vided into 4 chambers (Croco-dile has 4 chambered heart).Mammals and birds also havefour chambered hearts.

The deoxygenated blood (im-pure blood) from the bodycoined by two large veinscalled Superier Venacava andInferior Venacava is in theright auricle.

The oxygenated blood fromthe lungs is received by theheart in left auricle.

Aorta is the largest arterywhich carries oxygenatedblood.

The largest blood vessel in thebody is Aorta.

As blood passes throughlungs, gases are exchangedthrough blood vessels calledcapillaries of alveoli. Heartbeat rate in embryo (Foetus) 1minute = 200. Heart beat ratein new born baby 1 minute =140 times.

Normal pulse rate of healthyadult human is 72 per minute.

Normal BP is 120/80 mmHg. The science dealing with the

study of the heart and its dis-eases is known as cardiology.

ECG (Electro Cardio Gram)It is the photographic recordof electric variations that oc-cur during contraction ofmuscles of heart.

ECG was invented by WilhelmEinthoven.

Arteries carry pure blood fromthe heart to the tissues.

Pulmonary artery is the onlyartery carrying impure blood.

Veins collect impure bloodfrom the tissues and carry itto the heart.

Pulmonary vein is the onlyvein carrying pure blood.

The largest vein in humanbody is called inferiorvenacava.

The length of our bloodcapillaries is about 1,00,000cm.

Jarvik Heart is the artificalpump to replace the humanheart developed by Robert K.Jarvik.

John H. Gibbon (USA) builtthe first successful heart-lungmachine.

A pacemaker is used to stimu-late the heart muscles.

Except heart all other organsof our body are found in pairs.

The organ which is not af-fected by tumour is heart.Pain in heart musles -- Anginapectoris.

The circulation of blood in thebody is regulated by the heart.

The credit of discovering thecirculatory system goes toWilliam Harvey.

World’s first heart transplant was

performed on 3rd December 1967 by Christian

Bernard. Dr. Venugopal of All India Institute of Medical Science

performed India’s first heart transplant on 3rd August 1994.

The first heart transplantation in the history of Kerala

was conducted at Cochin Medical Trust Hospital

under the guidence of Dr. Jose

Chacko Periyapuram.

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The total length of our bloodvessels is about one lakhkilometre.

Heart disease Coronary heart disease refers

to the failure of the coronarycirculation to supply adequatecirculation to cardiac muscleand surrounding tissue.

Coronary artery disease is adisease of the artery caused bythe accumulation ofatheromatous plaques withinthe walls of the arteries thatsupply the myocardium.Angina pectoris (chest pain)and myocardial infarction(heart attack) are symptoms ofand conditions caused bycoronary heart disease.

Cardiomyopathy is thedeterioration of the function ofthe myocardium (i.e., the actualheart muscle) for any reason.People with cardiomyopathyare often at risk of arrhythmiaand/or sudden cardiac death.

Cardiovascular disease is anyof a number of specificdiseases that affect the heartitself and/or the blood vesselsystem, especially the veinsand arteries leading to andfrom the heart.

Heart failure also calledcongestive heart failure (orCHF), and congestive cardiacfailure (CCF), is a condition thatcan result from any structuralor functional cardiac disorderthat impairs the ability of theheart to fill with or pump asufficient amount of bloodthroughout the body.

Hypertensive heart disease isheart disease caused by high

blood pressure, especiallylocalised high blood pressure.

Inflammatory heart diseaseinvolves inflammation of theheart muscle and/or the tissuesurrounding it.

Valvular heart disease isdisease process that affectsone or more valves of the heart.

Blood The blood serves to transport

and distribute materials withinthe body.

Distribution of enzymes is nota function of blood.

Blood circulation was discov-ered by William Harvey.

Since blood is found outsidethe cells it is called as extracellular fluid (ECF).

The pH value of human bloodis nearly 7.5.

The blood cholesterol level in100ml of blood in a normalperson varies between 150-250 mg

The liquid part of the bloodviz. the plasma constitutes55% of the total blood vol-ume.

Albumin, globulin and fi-brinogen are the plasma pro-teins.

Fibrinogen is concerned withCoagulation of blood.

The blood cells are of threetypes - Red blood cells (Eryth-rocytes), White blood cells(leucocytes) and the Platelets(Thrombocytes).

Red Blood Corpuscles (RBC )contain haemoglobin whichgives blood its red colour.Camel is the only mammal hav-ing nucleus in the RBC.

The abnormal rise in totalcount of RBC is called poly-cythemia.

Erythrocytes participate intransporting oxygen fromlungs to tissues.

CO2 is carried in both plasmaand RBC as bicarbonates.

RBCs are produced in the bonemarrow.

Spleen & liver destroy thedead RBCs in human body.Spleen is known as graveyardof RBC.

Spleen serves as a BloodBank (Reservoir of blood) inthe body.

The life span of RBC is about120 days.

Haemoglobin consists of ironcontaining pigment haem anda protein globin.

Haemoglobin, the respiratorypigment gives red colour toRBC.

Haemoglobin helps in trans-portation of oxygen.

Normal adult human male has14 grams of haemoglobin in100 millilitre of blood.

Constituents of thehuman body

In a normal man weighing 60 kgConstituent Weight Percent

of atomsOxygen 38.8 kg 25.5 %Carbon 10.9 kg 9.5 %Hydrogen 6.0 kg 63 %Nitrogen 1.9 kg 1.4 %Calcium 1.2 kg 0.3 %Phosphorus 0.6 kg .2 %Potassium 0.2 kg 0.06 %

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The condition when haemo-globin content of the bloodfalls below normal is termedanaemia.

The disease resistant con-stituent of blood is W.B.C.which produces antibodies.

Antigens are capable ofstimulating the formation ofantibodies.

WBC-White Blood Cor-puscles (Leucocytes) defendour body from disease caus-ing microorganisms.

The number of luekocytes permicro litre of blood is calledthe total count of WBC. It isnormally 5000 in humans.

Leukaemia, also called bloodcancer, is caused by the overproduction of WBCs.

Leucopenia is the diseasecaused due to decrease in thewhite blood cells count.

The proportion of R.B.C.and W.B.C. in human bodyis 600 : 1.

The life span of WBC is about5 to 21 days.

Platelets or thrombocytes areother blood cells. They per-form an important role in bloodclotting. They live only for afew hours.

Clotting of blood in blood ves-sels is called thrombosis.

The coagulation of blood invessels is prevented duringnormal condition by heparin.

Haemophilia is a hereditarybleeding disease due to inad-equate clotting of the blood.

Haemophilia sometimes re-ferred to as bleeder’s diseaseor 'christmas disease.'

A healthy person has 5-6 litresof blood in his body.

At a time of blood donationonly 300 ml of blood is used.

The normal blood pressure ofa healthy adult is 120/80 mmHg.

120 mm Hg is known as sys-tolic pressure and 80 mm Hgis known as diastolic pres-sure.

High blood pressure (Hyper-tension) is known as the si-lent killer.

Normal blood sugar level : 80-100mg/100ml of blood

Normal cholesterol 50-180 mg/100ml of plasma.

The largest leucocyte -Monocytes.

The smallest leucocyte -lymphocytes.

The leucocytes capable ofproducing antibodies are -lymphocytes.

The leucocytes which aremodified as scavenger cells are- Monocytes.

The leucocytes that are able toproduce the anticoagulantheparin are Basophils.

Functions of Blood• Supply of oxygen to tissues (bound to hemoglobin, which is

carried in red cells)• Supply of nutrients such as glucose, amino acids, and fatty

acids (dissolved in the blood or bound to plasma proteins(e.g., blood lipids))

• Removal of waste such as carbon dioxide, urea, and lactic acid• Immunological functions, including circulation of white blood

cells, and detection of foreign material by antibodies• Coagulation, which is one part of the body's self-repair mecha-

nism (the act of blood clotting when one gets cut to stop thebleeding)

• Messenger functions, including the transport of hormonesand the signaling of tissue damage

• Regulation of body pH• Regulation of core body temperature• Hydraulic functions

Blood pressureBlood pressure (BP) is the pres-sure exerted by circulatingblood upon the walls of bloodvessels, and is one of the prin-cipal vital signs. During eachheartbeat, BP varies between amaximum (systolic) and a mini-mum (diastolic) pressure.

Presence of blood in urine - Haematuria. Presence of haemoglobin in the urine - Haemoglobinuria. Presence of excess urea in the blood - Uremia Presence of excess proteins in urine - Proteinuria.

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PlasmaAbout 55% of whole blood isblood plasma, a fluid that isthe blood's liquid medium,which by itself is straw-yellowin color.

Plasma functions in transport,body immunity, prevention ofblood loss, retention of fluidin blood, maintenance of pH,uniform distribution of heat.

Hematological disorders Anemia: Insufficient red cell

mass (anemia) can be the re-sult of bleeding, blood disor-ders like thalassemia, or nutri-tional deficiencies.

Abnormal increase in WBCcount is known as leukemia orblood cancer.

Leukemia is a group of can-cers of the blood-forming tis-sues.

Abnormal decrease in totalcount of WBC is known asleucopenia

Non-cancerous overproduc-tion of red cells (polycythemiavera) or platelets (essentialthrombocytosis) may be pre-malignant.

Hemophilia is a genetic illnessthat causes dysfunction inone of the blood's clottingmechanisms.

Blood is an important vectorof infection. HIV, the virus,which causes AIDS, is trans-mitted through contact withblood, semen or other bodysecretions of an infected per-son.

Hepatitis B and C are trans-mitted primarily through bloodcontact.

Leonardo da Vinci's Vitruvian Man displays the proportions of a man.The Vitruvian Man is a world-renowned

drawing created by Leonardo da Vinciin the year 1487.

The drawing and text are some-times called the Canon ofProportions .It is stored in the Galleriedell'Accademia in Venice, Italy.The drawing is based on thecorrelations of ideal human

proportions with geometrydescribed by the ancient Romanarchitect Vitruvius

Bacterial infection of theblood is bacteremia or sepsis.Viral Infection is viremia. Ma-laria and trypanosomiasis areblood-borne parasitic infec-tions.

Blood clotting Blood platelets breakdown in

the vicinity of an injury andrelease an enzyme that causesformation of fibrin fromfibrinogen. Fibrin forms atangled mass of fibres which

shrink and form a hard clot toplug the opening of the bloodvessel to stop bleeding. Afterclotting occurs, a strawcoloured fluid called ‘serum’ isleft. This portion of bloodretains its liquid formindefinitely.

Haemophilia is a hereditarybleeding disease due toinadequate clotting of theblood.

Recipient Donor

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Liver

Gall B

ladde

r

Bile Duct Largest blood cell in human body - Monocytes Smallest blood cell in human body - Lympho cytes

Cardiovascular system: pumping and channelingblood to and from the body and lungs with heart, blood,and blood vessels.Digestive System: digestion and processing food withsalivary glands, esophagus, stomach, liver, gallblad-der, pancreas, intestines, rectum, and anus.Endocannabinoid system: neuromodulatory lipids andreceptors involved in a variety of physiological pro-cesses including appetite, pain-sensation, mood, mo-tor learning, synaptic plasticity, and memory.Endocrine system: communication within the bodyusing hormones made by endocrine glands such asthe hypothalamus, pituitary or pituitary gland, pinealbody or pineal gland, thyroid, parathyroids, andadrenals or adrenal glandsIntegumentary system: skin, hair and nailsImmune system: the system that fights off disease;composed of leukocytes, tonsils, adenoids, thymus,and spleen.Lymphatic system: structures involved in the transfer

Major organ systemsof lymph between tissues and the blood stream, thelymph and the nodes and vessels that transport it.Musculoskeletal system: muscles provide movementand a skeleton provides structural support and pro-tection with bones, cartilage, ligaments, and tendons.Nervous system: collecting, transferring and process-ing information with brain, spinal cord, peripheralnerves, and nervesReproductive system: the sex organs; in the female;ovaries, fallopian tubes, uterus, vagina, mammaryglands, and in the male; testes, vas deferens, seminalvesicles, prostate, and penis.Respiratory system: the organs used for breathing,the pharynx, larynx, trachea, bronchi, lungs, and dia-phragm.Urinary system: kidneys, ureters, bladder and ure-thra involved in fluid balance, electrolyte balance andexcretion of urine.Vestibular system: contributes to our balance andour sense of spatial orientation.

Blood Groups A person having blood type

B could safely donate bloodto persons with blood type Band AB

Blood groups A, B, AB and Owere discovered by KarlLandsteiner.

O blood group can be givento persons of any other group.Therefore O group is calleduniversal donor.

A person with group AB canreceive any other group. SoAB is called universalrecepient.

‘A’ blood group is most com-mon among the Europeans,while ‘B’ and ‘O’ are commonamong the Asians and theAmerican Indians, respec-tively.

Erythroblastosis foetalis ––caused by the Rh bloodgroup.

Land Steiner and Weiner firstfound the Rh factor in Rhesusmonkey.

Normal count level RBC inBlood - 5 million/ccg Blood.

Normal count level WBC inBlood - 5,000 to 9,000 ccgBlood.

Normal count level platelets inBlood - 2,50,000 to 3 lakhs.

Life span of RBC - 120 days Life span of WBC - 5 to 21

days Life span of platelets - 7 days The instrument used to mea-

sure the blood pressure inHuman body - Sphygmoma-nometer

The only one vein in human

body which carries pure bloodis pulmonary vein

Antigen is a substance whichstimulates formation of anti-body

When the right ventricle in thehuman heart contracts, theblood moves to pulmonaryartery

Liver : The largest gland The liver is the largest gland

in the body.

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It is the largest metabolic or-gan in human body.

The liver is on the right sideof the stomach.

Liver is dark brown in colour. Sleeping on left side is useful

because it gives maximum re-laxation to the muscles of theright side and keeps the liverwarm and relaxed and im-proves bile secretion.

Glucose is stored in the liverand muscles in the form ofglycogen.

Liver is otherwise calledHEPAR.

Second largest gland in hu-man body - Pancreas

Exocrine and endocrine gland- Pancreas

Heterocrine gland -Pancreas A Normal man secrete about 1

Litre of Pancreatic Juice perday.

The main function of the liveris to produce bile which is animportant agent in digestionof fat.

There is no known digestiveenzymes in the bile.

Bile is stored in the gall blad-der.

Bilirubin and biliverdin arebile pigments.

The disease which affects theliver is jaundice.

Bleeding in liver is known asliver cirrhosis.

Hepatatis is the viral diseaseof liver which influence func-tioning of liver.

Excessive alcoholic consump-tion causes cirrhosis

Exessive stimulus for alcoholconsumption is called dypso-mania.

Manufacturing of urea takesplace in liver.

Excessive use of tobacco affe-cts the nerves while the sameof alcohol affects the liver.

Stone in gall bladder calledCholecystostatis

Urea is produced in the liver. Hepatitis is the viral disease of

liver which influencefunctioning of liver.

The weight of liver in man isabout 1.5 kg.

The disease that result due toany obstruction in the bile ductis Jaundice.

Excessive alcoholic consumption causes cirrhosis.

The high tendency to drinkalcohol is termed asdipsomania.

Liver has a great manyimportant functions other thanhelping in digestion. They are:

1) Regulation of carbohydrate,protein and lipid metabolism.

2) Synthesis of urea for excretion.3) Removal of drugs and toxic

materials. The liver hasenzymes which can detoxifyharmful materials.

4) Storage of vitamins.5) Liver is the principal organ for

the excretion of cholestrol, bile

pigments (bilirubin andbiliverdin) and inactivatedproducts of steroid hormones,some vitamins and many drugs.

6) Destruction of dead cells andbacteria by phagocytosis.

7) Synthesises heparin - ananticoagulant, prothrombin,fibrinogen and some factorsnecessary for bloodcoagulation.

Kidneys and Dialysis

The kidneys are the chief ex-cretory organs of vertebrates.

The main purpose of the kid-ney is to separate urea, min-eral salts, toxins, and otherwaste products from the blood.

Urea is removed from the bloodby kidneys.

The volume of urine producedin an adult human being forevery 24 hours is 6.5 litres.

The functional unit of kidneysis called nephron.

Nephritis is the inflammationof the kidney caused by theinfection of streptococci.

Presence of urea in the bloodis called uremia.

Kidneys are responsible forthe removal of excess water,salts and waste products fromthe blood in the form of urine.

Increased flow of urine iscalled diuresis and substa-nces that increase the flow ofurine is called diuretics.

Liver plays a major role in

metabolism and has a number

of functions in the body, in-

cluding glycogen storage,

decomposition of red blood

cells, plasma protein synthe-

sis, hormone production, and

detoxification. It lies below

the diaphragm in the abdomi-

nal-pelvic region of the abdo-

men. It produces bile, an al-

kaline compound which aids

in digestion, via the emulsifi-

cation of lipids.

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Cerebellum is known as‘Little brain’ of the entire

brain portions.

Anti Diuretic hormone (ADH)or Vasopressin regulates theamount of water excreted inurine.

Deficiency of ADH results inthe disease diabetes insipiduscharacterised by a largeamount of water being re-moved through urine.

Increased flow of urine iscalled diuresis and sub-stances that increase the flowof urine is called diuretics.

Dialysis is used in the case ofa patient suffering from kid-ney trouble

A dialysis unit is an artificialkidney which performs thefunctions of a normal kidneyoutside the body.

Dysuria is called painful Uri-nation.

The right kidney sits just be-low the diaphragm and poste-rior to the liver, the left belowthe diaphragm and posteriorto the spleen.

Each adult kidney weighs be-tween 125 and 170 grams inmales and between 115 and155 grams in females.

The kidney has a bean-shaped structure, each kidneyhas concave and convex sur-faces.

Outer darker region of kidneyis named as cortex.

Inner pale region of eachkidney is known as medulla.

Urinary bladder and ureters arelined by transitional epitheliumand hence are capable of beingconsiderably stretched, whenfilled with urine.

Normal urine is about 95%water and 5% dissolved solids.

Presence of glucose in urine isreferred to as glycosuria.

The kidneys excrete a varietyof waste products produced bymetabolism. These include thenitrogenous wastes urea, fromprotein catabolism, and uricacid, from nucleic acidmetabolism.

The kidneys secrete a varietyof hormones, includingerythropoietin, calcitriol, andrenin.

At least one kidney mustfunction properly for life to bemaintained.

Nephropathy refers to damageto or disease of the kidney. Anolder term for this is nephrosis.

Diabetes is the most commoncause of kidney failure,accounting for more than 40percent of new cases. Highblood pressure, orhypertension, is a major factorin the development of kidneyproblems in people withdiabetes.

Brain The brain is protected by

cranial bone and meninges. The brain is marked into

forebrain, mid brain and hindbrain.

The forebrain consists of ce-rebrum, the largest part of hu-man brain.

Cerebral cortex is outer layerof cerebrum. It is made of greymatter and contains many lay-er of nerve cells.

Cerebral hemisphere is divid-ed into frontal, parietal, tempo-ral and occipital lobes.

The surface of cerebral hemi-sphere shows many convolu-tions called Gyri separated bydepressions called Sulci.

The Gyri increases the surfacearea of cortex to accommodatemore nerve cells.

The general sensory orsomaesthetic area in parietallobe perceive generalsensation, viz pain. touch andtemperature.

The motor area in frontal lobecontrols voluntary movementof muscles.

The premotor area in frontallobe is the highest centre ofinvoluntary movements ofmuscles.

The visual and auditory areasare in occipital lobe and arecentres for visual and hearingsensation.

Association area in the frontallobe is responsible forassociation between varioussensations and movements.

Memory, intelligence, andjudgement depends on co-ordinated and integratedactivities of different corticalcentres.

Hypothalamus : contain highernerve centres for temperature

Some of the most commonkidney diseases and

conditions are: polycystickidney disease, nephrosis,lupus nephritis, diabetic

nephropathy,rhabdomyolysis, kidneystones, and renal tubular

acidosis.

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regulation, hunger, thirst andemotional function. It secretesneurohormones which controlsecretions of anterior pituitaryhormones. It synthesises theposterior pituitary hormones.

The medulla oblongatacontrols the involuntaryactions.

The central control ofrespiratory activity in humanbody is exercised by medullaoblongata.

Medulla oblongata has thecentres, for regulating theworking of the heartcontraction of blood vesselsand respiratory and digestivemovements.

The thermoregulatory centreof the human body ishypothalamus.

E.E.G (Electro Encephalogram)is used to record changes inthe electric potential in variousareas of brain.

Biological death of a patientmeans the death of tissues ofthe brain.

Encephalitis is caused byvirus.

Disorder of brain affectingrecognition of letters andwords is Dyslexia.

The final weight of the brain inan adult male is 1.4kg and 1.3kg in case of a woman.

Cerebellum is second largestportion of brain located at thebase, under the cerebrum.

Cerebellum contains centresfor the maintenance of postureand equilibrium of body andfor the muscle tone. It alsomodulates and moderatevoluntary action initiated bythe cerebral cortex.

Brian stem consists of ponsand medulla oblongata. Itcontrols vegetative actions.

Spinal Cord The spinal cord controls reflex

actions in human beings. The length of the spinal cord

is about 1 metre (3.3ft) The spinal cord is a series of

31 sections called segments.Each segment giving rise to apair of spinal nerves.

10 pairs originate from thebrain stem. It contain sensory,mixed and motor nerves.

We lose consciousness ifblood flow to the brain is cutoff for more than five seconds.

There are 12 pairs of cranialnerves and 31 pairs of spinalnerves in man.

SENSE ORGANS The organs which receive the

external and internal stimuliand convey the same to thecentral nervous system arecalled sense organs.

Smell Receptors for smell occur in

nasal mucosa and are made upof modified pseudo stratifiedepithelium. This epithelium isknown as olfactory epithelium.

Olfactory epithelium is moreextensive in dogs with an acuteolfactory sense.

This epithelium is composed ofthree types of cells - olfactoryreceptor cells, supporting cellsand basal cells.

Olfactory receptor cellsfunction as chemo receptors.

In order for a substance to be

smelled, the substance must becapable of entering to a gaseousstate to reach nostrils and itmust be water soluble todissolve in the mucus to makecontact with olfactory cells.

Taste Taste buds are sense crayons

for taste sensation. Taste buds are oval bodies

found as some elevation intongue called papillae.

Human beings recognise fourbasic modalities or tastes-sweet, sour, salty and bitter.

They are principally perceivedat the tip, along lateral edges,on upper surface of front halfand on the back of the tongue,respectively.

Sour taste is evoked by H+ions, produced by ionisationof acids.

Sweet taste is evoked byorganic substances viz. sugar,dextrin, glycerol, chloroform,aspartame and saccharine.

Bitter taste is evoked byquinine, morphine, caffeine,nicotine, urea and cation ofmany inorganic salts likeMagnesium salts.

Salty taste is evoked fromcations of Na+.

Scientific classification

of Human Being

Kingdom: ................. Animalia

Phylum: ....................Chordata

Class: ..................... Mammalia

Order: ........................ Primates

Family: .................. Hominidae

Subfamily: ............. Homininae

Tribe: ....................... Hominini

Genus: .......................... Homo

Species: ............Homo Sapiens

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Aspartame & saccharine arewidely used as ar tificialsweetening agents.

Loss of smell reduces theperception of taste also. Thatis why people suffering fromcold (rhinitis) often complainthat they cannot taste theirfood.

Taste of chillies, black pepperand hot sauces are not truesensation. It is mainly asensation of pain receptors.

Many insects such as honeybee, flies, butterflies and mothposses chemoreceptors fortaste sensation at their feet.

Some mammals like rhesusmonkey, dogs, pig and catpossess taste sensation forwater.

Man doesn’t possess tastebuds for tasting water.

Skin - Touch Skin : Touch corpuscle in the

skin responds to physicalsensations of pressure, heat,cold, contact and pain.

Skin is our tactile (sense oftouch) sense organ.

It is the largest organ of thehuman body.

In an adult man skin covers themuscles of about 1.9m2 (20sq.ft) and a woman has about1.6m2 (17sq.ft).

The outer layer of the skin istermed as epidermis, which hasno nerves or blood vessels andis continuously renewed.

Inner layer, called dermis, is athick layer below the epidermiswhich contain nerves, bloodvessels, hair follicles,sebaceous gland and sweatglands.

Colour of the skin is due to thepresence of the pigment,melanin, in epidermis.

The main function of humanskin is excretion.

Sweat serves to regulate thebody temperature.

Sweat glands seen in dermislayer help to eliminate excessheat from the body.

Dermatology is the branch ofscience that deals with thestudy of skin and its diseases.

EYE - Vision The eye (photoreceptor) is a

globular ball like organ situat-ed in a bony cavity, the orbit,of the skull.

Facts about Human BodyLargest and Longest bone in a man .......................................................................... Femur (thigh bone)Smallest muscle ..................................................................................................................... StapediusSmallest bone .......................................................................................................... Stapes (middle-ear)Total amount of blood in body ................................................................. 5.6 litres (1/15 of body weight)Life span of RBC ..................................................................................................................... 120 daysNumber of RBC's ...................................................... in male 5000,000 /cu.mm /in female 45,00,000/cu.mmNumber of WBC's ...................................................................................................... 5000-10000/cu.mmLife Span of WBC..................................................................................................................... 2-5 daysHeart beats ...................................................................................................................... 72 per minuteAverage amount of haemoglobin ..................................................................... 14-15 mg/100 ml of bloodThinnest skin ......................................................................................................... Conjunctiva (eyelid)Largest endocrine gland ................................................................................................. Thyroid glandLongest cell in body .............................................................................................................. Nerve cellSmallest cell in human body ................................................................................................... Sperm cellLargest cell in human body .......................................................................................................... Ovum

The eyeball has a diameter of2.5 cm.

The eyeball has 3 coatings Outer most layer is an opaque,

white, fibro elastic capsulecalled sclera. This is continu-ous with a transparent layercalled Cornea (bulging whitepart of the eye)

The membrane that coverscornea is conjunctiva.

In case of eye transfer onlycornea is used.

Middle layer is called choroid,is a highly vascular, pigmentedlayer.

Ciliary body is the thickestportion of vascular tissue,arising from a point just behindthe junction of sclera andcornea. It consists of ciliaryprocess and ciliary muscles.

A pigmented, muscular,opaque diaphragm called, Iris,extend from ciliary body infront of lens. It can be seen asa black screen through thecornea and has a small centralaperture called ‘Pupil’.

The iris has two sets of smoothmuscles arranged circularly.The pupil is constricted and

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dilated respectively by theirconstruction, to reduce andincrease the amount of lightfalling on the lens.

In bright light the irisautomatically shuts tighter,reducing the amount of lightentering the pupil.

In front of the eye there is aconvex lens. The lens isattached to the ciliary bodiesby suspensory ligaments.

Retina is the inner most layer,sensitive and made up of manycells and fibres.

Retina acts like the film incamera. In order to form animage on the retina, light mustpass through all the media ofeye (cornea, aqueous humour,lens, vitreous humour)and itmust be brought to focus onthe retina to form an upsidedown image on it.

The interpretation takes placein the brain.

The image formed on theretina of the human eye is realand inverted.

Eye contain receptors calledphotoreceptors viz ‘rods’ and‘cone’ cells, which convert theenergy of specific wavelengthinto action potential of nervefibre.

Nerve impulses are carried fromrods and cones by bipolarnerve cells to the ganglioncells. The axon of the ganglioncells converge and leave theeye ball to form ‘optic nerve.’

The spot at the back of eye,from where the optic nerve fibreleaves is covered by a zone ofretina free from rods andcones. So this spot is devoid

of ability for vision and is calledBlind Spot.

Lateral to blind spot, there is adepressed area of retina, calledFovea, which contains onlycones and no rods. Ability ofvision is highest in fovea.

The anterior compartment isfilled with aqueous humour. Itsupplies nutrients to lens andcornea having no bloodsupply, maintain shape ofcornea and support the lens.

The posterior compartment isfilled with transparentgelatinous material calledvitreous humour, whichsupports the lens and retina.

Colour blindness is a heredi-tary disease.

Squint eye is another eye de-fect which can be corrected byan operation.

The parts of eye involved ineye transplantion surgery arecornea, sclera and vitreoushumour.

The loss of vision during dimlight is called nightblindness.

Twenty-twenty means perfectvision.

SOME OF THE EYE DEFECTS Myopia: Also known as near

sightness or short sightness.Near object is clear. Far object isnot clear Eyeball become longer.Image is formed in front ofRetina. Can be remedied by con-cave lens.

Hypermetropia: Also known aslong sightness or far sightness.Far object is clear, near object isnot clear. Eye ball become short.Image is formed behind theRetina. Can be remedied by con-vex lens.

Astigmatism: Curvature of cor-nea become irregular and imageis not clearly formed. Remediedby cylindrical lens.

Glaucoma: It is due to increaseintra ocular pressure in aqueouschamber. Operation is needed atearly stage.

Trachoma: It is increased inRedness of eye and more secre-tion of watery fluid. It is due toinfection of bacteria, chlamidiatrachamastis. Due to this fol-licles may form in conjunctiva.

Xerophthalmia: It is due to de-ficiency of vitaminA. (A2). Dur-ing this conjunctiva or corneabecomes Keratinized. It maylead to blindness.

Strabimus: In this type eyeballremain in somewhat bent posi-tion which is due to long ocularmuscles formed during develop-ment of eye. Operation is neededat early stage. Also associatedwith squint.

Presbiopia: During this powerof accommodation of lens de-creases due to age factor anddefected metabolism. Alsoknown as age sightness. Can beremoved by bifocal lens.

Photofobia: No clear image inbright light.

Emmetropia - Normal vision Cataract - is the condition where

lens became opaque which isdue to defective protein metabo-lism leading to blindness. It maybe due to disease or old age. Itis remedied by replacing lens.

Colour blindness: It is knownas daltonism. It is the inability

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to distinguish between red andgreen colour. It is a sex linked (x-linked) genetic disorder.

Night Blindness: During thisRhodopsin is not resynthesizedwhile it is regenerated in dimlight.

Ear - Hearing The ears have two main func-

tionsi) Detection and analysis of

sound.ii) Maintenance of balance

of the body. Ear has three main regions - the

outer ear, the middle ear andthe inner ear.

External ear consists of pinnaand external auditory canal.

Pinna is a funnel shapedcartilaginous flap. It collectsand directs sound waves intoear canal.

The external canal ends at adelicate membranous diaphra-gm, called eardrum or tympanicmembrane.

The middle ear is an air- filledchamber. It communicates withthat of the pharynx through anair filled tube called, Eusta-chian tube.

Eustachian tube helps toequalize air pressure on eitherside of ear drum and thusallows it to vibrate freely, whensound waves impinge on it.

The vibrating eardrum trans-mits the vibration to the earossicles. Ear ossicles consistsof the hammer (malleus), theanvil (incus) and the strip(stapes). The stapes is thesmallest bone in the body.

The ossicles transmit thevibration to the inner ear,where they cause waves in thefluid called perilymph.

Perilymph is filled in the coiled,tube called cochlea, in themiddle ear.

Cochlea is a tube coiled, like asmall snail shell, of 2½ turns.

The sensory structuresrespond to different frequency,found on basilar membrane isthe rods or corti.

The internal ear is made up ofbony labyrinth andmembranous labyrinth. Thebony labyrinth contains a fluidcalled perilymph.

Endocrine Glands &Hormones

Largest endocrine gland -Thyroid.

Thyroid gland is popularlyknown as Adam’s Apple.

Hormones are chemicalsubstances produced byendocrine glands (ductlessglands).

Endocrine hormone moleculesare secreted (released) directlyinto the bloodstream, whereasexocrine hormones (orectohormones) are secreteddirectly into a duct, and, fromthe duct, they flow either intothe bloodstream or from cell tocell by diffusion in a processknown as paracrine signalling.

Glands are the organs of thehuman body whichmanufacture some liquidproducts which are secretedfrom the cells.Largest gland in our body isthe liver.

Types of glands - There are twotypes of glandsi. Ducted glands - exocrineglands, ii. Ductless glands -endocrine glands.

Deficiency of Parathyroidhormone (PTH) secreted byparathyroid gland causestetany in which calcium levelin blood decreases.

Adrenal glands are situatedover the kidneys.

Adrenal gland has two parts,Adrenal cortex and Adrenalmedulla.

Blood pressure is controlledby Adrenal gland

Adrenal medulla producestwo hormones- adrenalinand nor- adrenalin.

Adrenal gland prepares the ani-mal to fight or flight.

Adrenaline hormone raisesthe rate of heart beat andblood pressure.

The hormone secreted when aman gets feared is adrenaline.

Deficiency of insulin leads toexcess sugar in the blood andthis sugar is excreted in theurine. This disease is knownas diabetes mellitus (hyperglycaemia)

The main function of insulinis to control the level of sugarin the body.

Pituitary gland is an endo-crine gland attached to thebase of the brain.

The pituitary gland is called'the master gland' in the bodybecause it controls all otherendocrine glands present inthe human body.

Water balance in the body is

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mainly controlled by the se-cretion of ADH (Anti DiureticHormone) by hypothalamus

Endocrine andExocrine System

The secretions which theendocrine glands produce, do notleave the gland through a duct butpass directly from the cells to theblood stream. The organ in the body which

accumulates iodine is thyroidgland.

Insufficient iodine in the dietresults in the deficiency of thethyroid hormone, thyroxine.

Thyroxine deficiency in bodyresults in a disease calledsimple goitre.

Pancreas is an endocrine glandthat produces both an enzymeand a hormone.

The pituitary gland is called‘the master gland’ in the bodybecause it controls all otherendocrine glands present inthe human body.

Water balance in the body ismainly controlled by thesecretion of ADH (AntiDiuretic Hormone) byhypothalamus.

The normal value of bloodsugar is 80 to 120mg 100 ml ofblood.

Insulin prepared outside thebody is known as Huminsulin.

Thymus is another endocrinegland situated in front of thetrachea. Thymus secretes ajuvenile hormone, Thymosin.

Thymus gland becames fullydeveloped by about 7 years anddegenerates and disappearsafter 14 years of age because ofthe activities of the sex glands.

Pineal gland is anotherendocrine gland situated inbrain.Pineal gland secretesthe hormone melatonin andseratonin.Pineal gland is alsoknown as ‘Biological clock’.Exocrine Glands -

Ducted Glands Exocrine glands secrete their

product through well definedducts.

Liver is an exocrine gland,secretes bile in stomach.

Lachrymal gland secrete tearsin the eye.

Salivary glands secrete salivain the mouth.

Sweat glands seen on skin,secrete sweat.

Sweat is a mixture of sodiumchloride and Urea.

Spleen is the largest lymphaticgland in human body.

Enzymes Enzymes are complex chemical

substances consisting, wholelyor in a large part, of proteinsproduced in the living cells.

Enzymes are proteins thatcatalyze chemical reactions.

Some enzymes are usedcommercially, for example, inthe synthesis of antibiotics.Some household products useenzymes to speed up bio-chemical reactions

Coenzymes are small organicmolecules that transportchemical groups from oneenzyme to another.

Muscular Tissue It is a contractile tissue

consisting of very large cells.The unit of muscle tissue ismuscle fibre, which is made ofmyofilaments.

Based on structural andfunctional differences threetypes of muscles are reco-gnised. Unstriated muscles,Striated muscle and Cardiacmuscle.

Reproduction Reproduction is a process

by which an organism pro-duces new individuals or off-springs of its own species.

Sexual reproduction requiresone individual of each sex.

Testis is the sperm producingorgan of man.

The average period of humanpregnancy is 36-38 weeks -approximately 280 days

Mother’s milk contain 7% oflactose.

The part of the body thatcomes out first during delivery- head

Identical twins are formed,when the ovum after fertiliza-tion splits into two parts.

Sex chromosomes

In human beings sex chromosomes XX is present in females and

sex chromosomes XY is present in males. When X of female joins

X of male chromosomes the product will be a female baby (XX)

and when X of female joins Y chromosome of a male, the product

will be male baby (XY). That is the sex determination of a baby is

dependent on sex chromosome of man.

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Vasectomy - Sterilizationprocess in male.

Tubectomy - Sterilizationprocess in female.

Five principal methods ofasexual reproduction are:binary fission, multiple fission,fragmentation, budding andsporulation.

Human Reproductive System In the human reproductive

process, two kinds of sex cells,or gametes, are involved. Themale gamete, or sperm, and thefemale gamete, the egg orovum, meet in the female'sreproductive system to createa new individual. Both the maleand female reproductivesystems are essential forreproduction.

The organs which performsimportant functions inreproduction but neitherproduce gametes nor secretesex hormones are calledsecondary sex organs.

Secondary sex organs includethe prostate, seminal vesicles,vas deferens and penis, inmales. In females, secondarysex organs include fallopiantubes, uterus, vagina andmammary glands.

Extra-abdominal testes are thetestes of human males.

Testes is the male reproductiveorgan. The sperms areproduced by spermatogonia.

The male sex hormone, testo-sterone, is produced by Leydigcells.

The copulatory organ in maleis the Penis.

Female reproductive systemconsists of a pair of ovaries, apair of oviducts, the uterus, the

vagina, accessory genitalglands and the mammaryglands.

Graffian follicle produce ahormone estrogen.

The external genital organs offemales are collectively calledvulva. Clitoris is the vestigealpenis in female.

Important sexual hormones offemales include estrogen andprogesterone.

An important sexual hormoneof males is androgen, andparticularly testosterone.

When the male ejaculatesduring intercourse, semen isdeposited into the female'svagina. From the vagina thesperm make their way upthrough the cervix and movethrough the uterus with helpfrom uterine contractions. If amature egg is in one of thefemale's fallopian tubes, asingle sperm may penetrate it,and fer tilization, orconception, occurs.

Bones Human skeleton is made of

bones and cartilages. Largest and longest bone is

femur (thigh bone). The shortest bone in the

human body is stapes orstirrup bone in the middle ear.

Human bones are made up ofCalcium phosphate and Cal-cium carbonate.

The total number of bones inhuman skull is 29.

The total number of bones inan adult human body is 206.

A new born baby has 300bones, but 94 bones fuse to-gether as it grows.

There are 24 ribs in humanbody.

The total number of ear bonesare six.

In an adult human being, thenumber of vertebrae is 26. Neckregion of human has 7 bones.

The face of a man is made upof 14 bones.

Phosphate of lime forms 51%of bone.

The bones contain calciumphosphates upto 85%

The smallest bone in the hu-man body is the stapes (stir-rup) found in the middle ear.

Bone marrow contains the par-ent cells that give rise to bloodcells.

'Funny Bone' is a nerve at theback of the elbow.

Cranium is the Brain box thatencloses brain

Ethmoid is the bone of Nasalchamber

The total number of bones inthe skull is 29.

Disorders of Bone The bones of aged persons are

more fragile than the bones ofyoung persons.

The breaking of a bone isknown as fracture.

When the person feels acutepain at the joints, particularlywhile moving the joints, isreferred to as arthritis.

Osteoarthritis is commonlyknown as ‘‘wear and tear’’arthritis.

Osteoporosis is another bonedisorder common in womanover 50 years, and ischaracterised by decreasedbone mass and increasedsusceptibility to fractures.

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Teeth There are 20 milk teeth in hu-

man body. A full set of permanent teeth

consists of 32 teeth. The hardest material found in

human body is enamel. Milk teeth appear by the age

of 7 months, adult teeth ap-pear from 6th year onwardsand wisdom teeth appear be-tween the ages of 17-30 years.

Fluorides are the compoundsthat prevent tooth decay.

One of the ingredients oftooth paste is calcium fluo-ride.

Enamel is the hardestsubstance in the body.

Skin Skin is the largest organ in

human body. Colour of the skin is due to

the presence of melanin. The main function of human

skin is protection and excre-tion.

Perspiration is an usual way

Important VaccinesVaccine ......................................... Name of the ScientistSmall pox ....................................... Edward Jenner (1786)Cholera ......................................... Louis Pasteur (1880)Diphtheria and tetanus .................. Emil Adolf Von Belming

and Shiba saburo kita sato.TB Vaccine .................................... Leon Calmatte and

Camille Guerin.Polio Vaccine ................................. Jonas E. SalkMeasles Vaccine ............................ John F. Enders

National Research Institutes in IndiaCentral Drug Research Institute ................................. Lucknow (U.P)Cattle Breeding Research Institute .......................... Hissar (Haryana)National Dairy Research Institute ............................ Karnal (Haryana)Forest Research Institute .......................................... Dehradun (U.P)Centre for Cellular and Molecular biology ...................... HyderabadIndian Cancer Research Centre .......................................... MumbaiCentral Marine Research Institute ...................................... ChennaiCentral Public Health Engineering Research Institute ........... NagpurNational Institute of Communicable Diseases ..... Delhi

of the body to maintain thebody temperature. Sweatglands help to eliminate excessheat from body.

Dermatology is the branch ofscience that deals with thestudy of skin and its diseases.

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Genetics Genetic engineering is the

branch of Science. Genetics is the science of

genes, heredity, and variationin living organisms.

A gene is the fundamental bio-logical unit which is transmit-ted from one generation to thenext. It is the unit of heredity.It remains at a definite posi-tion on a chromosome. In manabout 1,00,000 genes areknown to be found in 23 pairsof chromosomes.

Genetics deals with heredityand the laws that govern it.Rev. Gregor Mendel is the'Father of Modern Genetics.'

Mutation is the process ofsudden heritable change un-dergone in a gene due tochange in its composition.

Mutation is a change that isinherited

DNA (Deoxyribo nucleic acid)is the principal genetic mate-rial of all living beings.

The structure of DNA mol-ecule was discovered byWatson and Crick in 1953.

Recombinant DNA involvestransplanting a piece of DNAof one organism to the DNAof another, which finds appli-cation in the production of In-terferon and Insulin.

DNA has a double helicalstructure of nucleotide chainsconsisting of deoxyribosesugar and nitrogen bases-Adenine, Guanine, Thymineand Cytosine. It stores andtransfers hereditary informa-tion and creates its own rep-lica.

Father of Modern GeneticsRev. Gregor Mendel was the

Augustinian priest and scientist. Thetheories of heredity attributed to GregorMendel, based on his work with pea plants.Experiments with Plant Hybrids, in whichMendel described how traits wereinherited, has become one of the most enduring and influentialpublications in the history of science.

Mendel’s study showed that one in four pea plants hadpurebred recessive alleles, two out of four were hybrid and oneout of four were purebred dominant. His experiments broughtforth two generalizations, the Law of Segregation and the Lawof Independent Assortment, which later became known asMendel’s Laws of Inheritance.

The nitrogen base Thymine inDNA is replaced by Uracil inRNA.

RNA has sub-species m-RNAand t-RNA, which carries thestored information of the DNAfor translation into variousproteins.

In protein synthesis, the ge-netic code is carried from theDNA of the nucleus to the ri-bosomes of the cytoplasm bym-RNA.

DNA fingerprinting hashelped to solve many myster-ies and crimes.

The number of chromosomesin a human cell is 46.

Presence of an extra chromo-some in the foetus - mongol-ism.

The Bacteria which receivesgenes from another species iscalled Transgenic bacteria.

The genes transfer from onespecies to another speciesthrough Plasmids.

The gene with Bt.Toxin is iso-lated from BacillusThuringiensi’s Bacteria.

Bt. Cotton is the cotton plantwith Bt.Toxin gene.

DNA testing

DNA testing is used for identification of individuals on the basis

of their respective DNA profiles. It is also used for parental

testing and rape investigation. Although 99.9% of human DNA

sequences are the same in every person, enough of the DNA is

different to distinguish one individual from another. The DNA

testng technique was first reported in 1984 by Sir Alec Jeffreys in

England. Jeffrey’s technique of DNA fingerprinting is now

used to identify criminals in forensic laboratories. It is also used

to determine paternity or maternity, that is who the true biological

father or mother of a child.

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ECOLOGY Ecology is the scientific study

of the relation of plants andliving organisms to each otherand their surroundings.

Ecology is closely related tothe disciplines of physiology,evolution, genetics andbehavior.

Biodiversity describes allvarieties of life from genes toecosystems and spans everylevel of biological organization.

An ecosystem is the largestfunctional unit in ecologybecause it includes both living(biotic) and non-living(abiotic) environments.

June 5 is considered as WorldEnvironment Day.

Ecomark is given toenvironment friendly productsof BIS (Bureau of IndianStandards)

Ecological friendly tourism istermed ecotourism.

Prof. R. Mishra is called as‘Father of Ecology in India’.

The rich source of energywhich never causesatmospheric pollution is solarenergy.

The conditions under whichan organism lives constitute itsenvironment. A few physicalfactors that greatly influencethe environment are Light,Temperature, water and gases.

A biome is a unit resulting fromthe interaction of a regionalclimate, animal and plant lifeand substrate. The types ofbiome are grasslands, deserts,coniferous forests, deciduousforests, tropical forests, tundra,fresh water and marineenvironment.

There are six major airpollutants : carbon monoxide,sulphur oxides, nitrogenoxides, particulates, hydrocarbons and photochemicaloxidants.

The mode of transfer of energyof food synthesised in plantsthrough a series of organismsof an ecosystem with repeatedeating and being eaten isknown as food chain.

The rich source of energywhich never causes atmo-spheric pollution is solar en-ergy.

The interlocking of many foodchains is called 'food web'.

A simple sequence in which thegrass grows, a cow eats thegrass, a human eats the cow ordrinks its milk, is an example offood chain

B.O.D means Biological OxygenDemand. The estimation of

Charles DarwinHe discovered a hypothesis for the originand continuation of life on Earth. Histheory is also called the Theory ofEvolution. Charles Darwin becamefamous when he hypothesized that alllife evolved from common ancestorsthrough evolutionary processes ofnatural selection. Darwin is the first ofthe evolutionary biologists, theoriginator of the concept of naturalselection – Theory of NaturalSelection.

Charles Darwin collected a largenumber of specimens and concluded that the Species

arose as a result of natural selection. He published his theory in hisbook On the Origin of Species (1859). "The Voyage of the Beagle"- another important book. "In the struggle for survival, the fittestwin out at the expense of their rivals because they succeed inadapting themselves best to their environment' - Charles Darwin.

B.O.D gives an idea of theamount of pollution in water.

B.O.D is measured as the weight(in mg) of oxygen that is con-sumed in 1 litre of water storedfor 5 days in darkness at a con-stant temperature of 200C.

Water pollution is caused bysewage, sullage and industrialeffluents.

The mass death of livingorganisms including man inone night at Bhopal (1984),was due to the leakage ofmethyl isocyanate (toxic gas)into the air from an insecticideplant managed by UnionCarbide.

Environmental planningorganisation is NEERI. NEERIis National Environment Engi-neering Research Institute. Itis in Nagpur.

First Earth Summit (1992) at Rio

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Global warmingGlobal Warming is the increase of the averagetemperature on Earth. As the Earth is gettinghotter, disasters like hurricanes, droughts andfloods are getting more frequent. It happenswhen greenhouse gases (carbon dioxide,water vapor, nitrous oxide, and methane)trap heat and light from the sun inthe earth’s atmosphere, whichincreases the temperature.Over the last 100 years, theaverage air temperature near theEarth’s surface has risen by alittle less than 1 degree Celsius or1.3 degrees Fahrenheit.Increase of one degree Celsius makes the earth warmer nowthan it has been for at least a thousand years.The top 11 warmest yearson record have all been in the last 13 years, said NASA in 2007, and thefirst half of 2010 has already gone down in history as the hottest everrecorded.Projections from the UN climate change body the IntergovernmentalPanel on Climate Change (IPCC) say that global surface temperature willprobably rise a further 1.1 to 6.4 degrees Celsius (2.0 to 11.5 degreesFahrenheit) during the 21st century.

de Janerio (Brazil) was relatedto conservation of genetic re-sources of plants and animals.

Second Earth Summit (2002) atJohannesburg (South Africa).

Petroleum, coal, fossil fuel etcare non-renewable sources.

Domestic wastes contain biode-gradable pollutants.

Most hazardous metal pollut-ant of the automobile exhaustis lead. Unleaded petrol is freeof lead.

Biomass is a renewable sourceof energy.

Ultra Violet rays are non-ionising radiations damagingto DNA.

Nuclear radiations may causecataract, an eye disease.

Strontium-90 (Sr90) causes leu-kaemia (blood cancer).

Radiation causes leukaemia. CSE – Centre for Science and

Environment

Origin & Evolution Life was present on the earth

about 3.9 billion years ago.Theories :-

(i) Special creation : This ideaembodies that life on Earth isdivine creation.

(ii) Spontaneous generation :According to this theory, lifeoriginates spontaneously fromlifeless matter ie. abiogenesis.However this idea has been putto rest when Louis Pasteur

provided proof that micro-organisms come only fromother micro- organism.

(iii) Cosmic origin : This notionadvocates that life could haveoriginated once or severaltimes in various part of galaxyin universe.

(iv) Terrestrial or Biogenic origin :This idea holds that life aroseby series of sequentialchemical reactions. This ismodern concept.

GreenhouseEffect

Greenhouse gases heat up

our planet. They are part of

Earth's atmosphere and trap

warmth emitted by the sun,

thus heating Earth. It is this

process – the greenhouse ef-

fect – that makes life on the

planet possible.

Natural greenhouse gases

like carbon dioxide, methane,

and nitrous oxide have al-

ways been in the atmosphere.

Without them, the world’s

average surface temperature

would be a chilly -18 degrees

Celsius. However, we enjoy

an average temperature of 14

degrees.

Tall grass grasslands of North America ................................ PrairieShort grass grass lands ...................................................... PlainsPlants of deserts ....................................................... XerophytesConiferous forests ...................................... Boreal forests (Taiga)Trees those shed their leaves ....................................... DeciduousTropical forests ........................................ Evergreen Rain forests.Tundra .......................................................................... Treeless

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Koppenhagen SummitThe 2009 United Nations Climate Change Conference, commonly known as theCopenhagen Summit, was held at the Bella Center in Copenhagen, Denmark.This was the 15th Conference of the Parties (COP 15) to the United NationsFramework Convention on Climate Change and the 5th Meeting of the Parties(MOP 5) to the Kyoto Protocol. The Koppenhagen Accord is a significant firststep in engaging the world's largest emitters in the global effort to slash carbonemissions.The Copenhagen Accord was drafted by the US, China, India, Brazil and SouthAfrica. Accord is not legally binding and does not commit countries to agree toa binding successor to the Kyoto Protocol, whose present round ends in 2012.

Kyoto protocol

The Kyoto Protocol is a protocol to the United Nations

Framework Convention on Climate Change (UNFCCC or FCCC),

aimed at fighting global warming. The UNFCCC is an international

environmental treaty. The Protocol was initially adopted on 11

December 1997 in Kyoto, Japan. The target agreed upon was an

average reduction of 5.2% from 1990 levels by the year 2012.

Radiation PollutionNuclear fuel cycle, combustion

of coal, accidents in nuclear powerplants, medical therapy anddiagnosis, scientific research,detonation of nuclear weapons intesting and war, television sets aresources of radiation. Foeteses aremore sensitive to radiation. Cancermay be increased by ionisingradiation. Ozone layer filters out solar

ultraviolet radiation which isharmful to most animal andplant life. 90% of ozone residesin stratosphere.

One chlorine atom can destroyabout 1,00,000 ozonemolecules.

Tetraethyl lead and tetramethyllead are used in automobilesas anti- knocking agent.

Lead, SO2, NO2 and COimpedes oxygen transport by

combining with Hb. The effect of particulate matter

depends on the size and fateof particles on our body.

The effect of gaseous pollutantdepends on their solubility inwater.

NO2 at high concentrationsimpairs functioning of lungs byaccumulating water in airspaces.

Polluted air cause respiratorydisorders such as bronchitis,emphysema and lung cancerespecially in children.

Fluorides destroy leaf tissues. Oxides of Nitrogen and

fluoride reduce crop yields. Hydrocarbon such as

ethylene causes prematurefalling of leaf, flower bud andcurling of petals.

Smaller particles are separatedfrom harmless gases bycyclone collector orelectrostatic precipitator.

The most important method ofconversion of pollutant isoxidation in air.

Sewage waste are always richin bacteria and organicsubstrate.

In organic nitrates andphosphates stimulateexcessive plant growth in lake.

The organochlorides inpesticides are highly persistentand pass through food chain.They accumulate in fatty tissueand affect the nervous system.

Change in colour is a verycommon effect produced bydyes, inorganic substanceslike chromium and ironcompound.

Noise is physical form ofpollution.

Kyoto protocol - To reduce theemissions of Green HouseGases (GHGs)

Montreal Protocol - To keepozone layer intact (To reduceCFCs)

Cartegena Protocol - Topreserve bio diversity &Biosafty protocols

Stockholm convention - Toreduce the use of POPs(Persistent Organic Pollutants)or Dirty Dozen

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Apes are represented by gibbons, orangutans,chimpanzees, and gorillas.

‘Homo sapiens’ appeared in either Africa orAsia 5,00,000 years back and spread out. Todayno other species is as widely distributed asanimals.

Neanderthal specimen of man is excavated fromNeander Valley of Germany. The Neanderthalslived 100,000 to 30,000 years ago. They werethe typical cave humans, short with heavybrows, retreating foreheads, large jaws, alumbering gait and stooped posture. They woreclothing and were good hunters.

‘Cro - magnon’ man bears the closestresemblance to modern man. He wascompletely errect, and 6 feet tall. He belongedto Stone Age. He is the most recent pre-historicman.

Dryopithecus, Ramapithecus, Australopithecus, and Homo erectus are prehumantypes, ranging from 20 million years to 12 millionyears back.

The fossil record of humans and other primatesis incomplete.

Modern man and apes are recent products ofevolution and both are thought to havedescended from a common extinct ancestralform. The view that humans evolved from apeshas been invalidated.

Primates are members of the order of mammalsthat includes monkeys, apes and human

(together called anthropoids) as well as lemurs,lorises and tarsiers, ( together called prosmians)

Generally they have forward directed eyes,gripping hands and feet opposable thumbs andbig toes. They tend to have nails rather thanclaws with gripping pads on the ends of the digits,all adaptations to the climbing mode of life.

Ramapithecus : Extreme reduction of canines,modification of the chewing teeth, to be muchstronger. Development of bipedalism :- walkingon two feet, and than an erect posture and freehands. Terrestrial living and balance of head onthe spinal column. Terrestrial gathering economy.

Australopithecus :- Walked erect with a curvedback Larger size of brain barrel like trunk withrobust build. Meat eaters and gathers, but stillnot hunters but scavenger.

Homo erectus : More rounded head, 5 feet inheight and had strong bones. Made stone tools,started hunting ‘Domesticated’ fire.

Homo Sapiens : More strengthened chewingmuscles more developed brain (all lobesdeveloped). Humans, known taxonomically asHomo sapiens.

Anatomically modern humans originated in Af-rica about 200,000 years ago, reaching full be-havioral modernity around 50,000 years ago.

The study of human evolution encompassesmany scientific disciplines, including physicalanthropology, primatology, archaeology, linguis-tics and genetics.

Evolution of Man

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Medical SciencePharmacy Small pox was the disease

that led to the discovery offirst antiviral vaccine.

Small pox is the only diseasetotally eradicated in 1980throughout the world by vac-cination.

Tetracyclins (antibiotics)helps to cure trachoma, an eyedisease.

Antibiotics are the drugswhich are produced by bacte-ria and which act against otherstrains of bacteria.e.g.penicillin,streptomycin,chloromycin.

Antihistamines are the sub-stances that relieve the symp-toms of asthma, hay fever andother allergies.

Antipyretics are the drugsused medically to lower bodytemperature.

Leprosy is also known asHansen's disease.

The vaccine, triple antigen isgiven to children to immunisethem against Diphtheria, Per-tussis (whooping cough) andTetanus.

Quinine is an alkaloid thatcures malaria.

Quinine is extracted from thetree ‘Cinchona officinalis.

Azidothymidine (AZT) is adrug used to combat AIDS.

To prevent polio, two vaccinesSabin (oral) and Salk (inject-able) vaccine are offered.

A drug that prevents infectionand decay is called an anti-septic.

LSD (lysergic acid diethyla-

mide) is a hallucinogenic drug. Eldepyl is a new wonder drug

to treat Parkinson’s disease (aneurodegenerative disease).

Aspirin (i.e., Acetyl SalicylicAcid) is commonly used as apain reliever.

The chief ingredient of themosquito repellant cream isderived from neem plant.

B.C.G. (Bacillus CalmetteGuerine) Vaccine is adminis-tered to prevent tuberculosis.

Tranquillizers are drugs tocalm the nervous system andprevent tension and worrywhile sedatives are drugsused to induce sleep.

Shanvac-B is India’s first in-digenous genetically engi-neered Hepatitis - B vaccine

Viagra is a tablet for stimulat-ing sex potential.

Morphine works as an anal-gesic drug and is classified asnarcotics.

An antibiotic is a substanceproduced by a living organ-ism, especially a bacterium ora fungus.

Penicillin is produced fromfungus known as Penicilliumnotatum.

CP-20-961 is a malarial vac-cine.

Diseases andTreatments

Avian influenza virus isresponsible for contagiousdisease “Avian flu” affectingbirds.

Avian flu is due to the mutatedgenes of H5N1 virus.

SARS is severe AcuteRespiratory Syndrome.

Euthanasia means mercy kill-ing. It was first introducedlegally in Netherlands and inBelgium second time.

Computer Axial Tomograph(CAT) scan is used for photo-graphing a selected plain ofthe human body using X-raysfor diagnosing the cause of adisease.

CAT Scan is also known asCT Scan.

CAT scanner was invented byGodfrey Hounsfield.

MRI-Scan means MagneticResonance Imaging Scan.

PET Scan is Positron Emis-sion Tomography scan. It isused for studying brain.

Otoscope is an instrumentused for examining the outerear and ear drum.

Physiotherapy is the treat-ment of diseases or disabili-ties by massaging and exer-cise.

Cancer Uncontrolled growth of cell,

which can be caused byOncogenes are cancers.

A biopsy is done in order todetect the presence of can-cer.

Biopsy means examination oftissue cut from living body.

Lithotripter is the machineused to break up kidneystones by ultra sound waves.

Oral Rehydration Therapy(ORT) is useful in combatingcholera, dysentery and gas-troenteritis.

In medicine, radioactive iso-topes are used as tracers fordiagnostic purposes.

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Diseases and Affected OrgansOsteomyelitis ................................................... Vertebral columnPolio ...................................................... Central nervous systemMalaria ............................................................................... RBCMeningitis ................................................. brain and spinal cordTyphoid .................................................... Intestine, whole bodyDiphtheria ........................................................................ throatBright’s disease .............................................................. kidneyEczema ................................................................................ skinHepatitis ............................................................................. liverJaundice ............................................................................. liverTuberculosis ..................................................................... lungsPneumonia ........................................................................ lungsGingivitis,pyorrhoea .......................................................... gumsGoitre ............................................................................. thyroidTrachoma ........................................................................... eyesArthritis ............................................................................ joints

Arsenic - 74 is used to detecttumours.

Sodium - 24 is incorporatedinto salt (NaCl) and used todetect the presence of bloodclots in the circulatory system.

Cobalt-60 is used in treatmentof cancer.

China is famous for the modeof medical treatment calledAcupuncture.

Anaemia is the shortage ofhaemoglobin in blood.

The number one killer dis-eases in the world are tuber-culosis and cardiovasculardisease respectively.

Pneumonia, gonorrhoea, tu-berculosis, tetanus (or lock-jaw), botulism, syphilis, ty-phoid, cholera, leprosy,plague, whooping cough etcare bacterial diseases.

Chickenpox, rubeola (Germanmeasles), measles, mumps, in-fluenza, common cold, AIDS,hepatitis, polio and rabies areviral diseases.

Protozoans cause amoebicdysentery, malaria, Africansleeping sickness, Kala-azaretc..

Fungi causes athelete’s footand ringworm.

Haemophilia, sickle cellanaemia and Huntington’sdisease (It is a hereditary dis-ease resulting in the involun-tary movement of body parts.)are congenital diseases (ie,present at birth).

Diphtheria is a disease ofthroat.

D.P.T. Vaccine (Triple Vac-cine) is used to prevent diph-theria, pertusis or whoopingcough and tetanus.

Rubeola is the medical nameof the disease measles.

Elephantiasis is caused by thenematoda ‘Wuchereriabancrofti’.

The vector of the disease fi-lariasis (elephantiasis) is culexmosquito.

Contagious diseases are dis-eases which spread from oneperson to another by physi-cal contact.

Infectious diseases are diseasescaused by a specific organismand spread through air, water,food, etc.

The loss of elasticity ofmuscles results in a diseasecalled Parkinson’s disease. Itwas invented by an Englishsurgeon namely JamesParkinson.

Malaria is caused by Plasmo-dium vivax.

Malaria is spread by femaleanopheles mosquitoes and itaffects the RBC.

Plague is spread by rat fleas. Dengue fever is spread by

Aedes aegypti mosquitoes. Tuberculosis, Smallpox and

Influenza are diseases thatspreads through air.

Tuberculosis is known as'White Plague.'

Tetanus can cause lock jaw. Cholera, typhoid, dysentery

and diarrhoea are water bornediseases.

Exophthalmic goitre is knownas grave’s disease.

Disease causing microorgan-isms are called pathogens.

The virus which attack bacteriais called bacteriophage.

Arthritis and rheumatism af-fect the joints.

Hydrophobia is a diseasecaused by the bite of a maddog. It is commonly known asrabies. It can be prevented byinjections discovered by Louis

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Pasteur. Injections are knownas ARV ( Anti-Rabies Venom).

Rabies is caused by a virus,and it affects the nerve cellsof the brain.

Alzheimer’s disease Amyloidbeta (A ) deposits are thefundamental cause of this dis-ease.

Trypanosomiasis is transmit-ted from animal to man by thetse-tse fly and causes thedreaded disease sleeping sick-ness. Kala-azar (Leishmania-sis) is transmitted bysandflies.

Hypothermia is the loss ofbody heat (below 31.70C).

People living in hilly areassuffer from goitre because ofthe lack of iodine in diet anddrinking water.

Minamata disease resultingfrom mercury poisoningcauses brain damage, birthdefects and death.

Virus is responsible forcommoncold, the diseasewhich affects largest numberof people in the world.

Miscellaneous Antigen is a substance which

stimulates the formation ofantibodies.

A colour-blind person has dif-ficulty in distinguishing be-tween green and red colour.This disease mainly affectsmales.

Hookworm enters the intes-tine by penetrating throughthe skin.

Amnesia is related to the lossof memory.

UV radiation also give us a sun

tan. But an excess is harmfuland can cause skin cancer anddamage to retina.

Test tube baby refers to thephenomenon, where the fer-tilization is external and devel-opment is internal.

World's first test tube babyLouise Brown was born on25th July 1978.

World health day is observedon April 7th.

Important Digestive EnzymesAmyalse, (ptyalin) Salivary glands in mouth Starch to maltosePepsin Gastric glands in stomach Proteins to peptonesTrypsin Pancreas in abdomen Proteins to peptonesAmylase Pancreas Carbohydrate to maltoseLipase Pancreas Fats to fatty acid and glycerol.Erepsin Intestinal glands in small intestine Peptides to amino acidsMaltase Intestinal glands maltose to glucoseLactase Intestinal glands lactose to glucoseSucrase Intestinal glands sucrose to glucose.

Common DrugsAnaesthetics Drugs that block sensory nerves and make a patient

fully unconscious to prevent him from feeling pain.Analgesics Drugs used to prevent or relieve pain like aspirin.Antibiotics Drugs used to prevent growth of bacteria or other

germs.Antihistamines These drugs are used to relieve symptoms of asthma,

hay fever and other allergies.Antipyretics Drugs used to lower body temperature.Hormones Drugs used to combat hormone deficiency that cause

diseases.Narcotics Drugs that deaden the nervous system and prevent a

person from feeling pain.Sedatives Drugs used to induce sleep, like barbiturates and

bromides.Tranquillizers Drugs that calm nervous system and prevent worry,

tension etc.Vaccines Drugs that are injected to help the body to develop

resistance to disease or immunization of the body.

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Agriculture The chemical contained in to-

bacco is nicotine in root. Quinine, Tannin and Cinna-

mon are obtained from thebark of the tree.

Tea leaves contain 18% tan-nin.

T x D and D x T are high yield-ing hybrid varieties of coco-nut.

Hybrid is an animal or plantthat has been bred from twodifferent types of animals orplants.

HYV means High Yielding Va-rieties.

Foot and Mouth disease oc-curs in cattle, sheep and pigs.

Cocoon stage of silkworm pro-duces silk.

Silk worms are reared on mul-berry.

The most important stimulantin coffee leaves is caffeine.

Opium is extracted from theimmature fruits of the plantpoppy(Papaver somniferum).

Paper is chemically cellulose. Sunflower oil has the maxi-

mum polyunsaturated fattyacids.

Mint is propagated throughrhizomes.

For safe storage, the moisturecontents of foodgrainsshould be less than 14%.

The acid present in the soiland substances formed by thedecomposition of decayedgreen matter is ‘humic acid.’

Fertilizers Azolla acts as biofertilizer in

association with the blue-greenalgae. It is used in the cultiva-tion of rice.

N.P.K. mixtures are fertilizerswith the mixtures of nitrogen,phosphorus and potassium.

Nitrogen helps in greening ofplants and their rapid growth.

Phosphorous helps in flower-ing of plants.

Potassium helps in the fruitforming stage in plants.

Salinity of soil can be neutral-ized by using pyrite and gyp-sum.

Iron is an essential micro-nu-trient required for the devel-opment of plants.

Blue-Green algae works as abio-fertilizer.

Pesticides Pesticides include insecti-

cides, fungicides, nemati-cides, rodenticides and herbi-cides.

D.D.T and Parathion pesti-cides are banned in most ofthe developed countries. Ma-jor drawback of D.D.T as apesticide is that it is not eas-

ily and rapidly degraded innature.

Biological control of insectsmeans control of insect popu-lation in exploitation of natu-ral prey-predator relationship.

D.D.T. (an insecticide) has atendency to remain stable inenvironment for long periods.

Bordeaux mixture is a fungi-cide.

BHC is Benzene Hexa Chlo-ride.

Loss of agricultural productiv-ity due to pests and diseasesis about 30%.

Sporeine is a bio insecticide.Sporeine was the first bio in-secticide to be developed ona commercial scale.

Natural insecticide 'azadira-ctin' is obtained from Neem.

The pesticide used in founda-tions of buildings for prevent-ing, termite attack is 'Aldrin.'

Forestry

Turpentine oil is obtained frompinus tree.

Sweet potato is a modificationof adventitious roots.

Plants and animals living in agiven area form a community.

Famous Botanical Gardens in India

Agri Horticultural Society of India, Alipore, Kolkata

Indian Botanical Gardens, Shibpur, Kolkata

Lalbagh, Bangalore, Karnataka

Government Botanical Gardens, Udagamandalam, Tamil Nadu

Jhansi Botanical Garden, Jhansi, Uttar Pradesh

Saharanpur Botanical Garden, Saharanpur, Uttar Pradesh

Lloyd's Botanical Garden, Darjeeling, West Bengal

Garden of Medicinal Plants, North Bengal University, West Bengal

Tropical Botanic Garden and Research Institute Palode Kerala

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Rain forests occur in Western Ghat and East-ern Himalayas.

Herbarium is a collection of 'preservedplants.'

The 'Great Banyan Tree' is in Indian Botani-cal Garden Sibpur, Kolkata.

Wild Life Protection Act was enacted in India in1972.

The threat of extinction of tigers forced the Indiagovernment to initiate the 'Project Tiger' on April 1,1973.

In India, paper is mainly manufactured fromBamboos.

Mango, Papaya, Banana, Guava, Pineapple,

Human Genome Project (HGP)HGP was launched in 1988, with the Nobel

laureate Dr. James D. Watson as the directorand the project envisaged.

The Human Genome Project originallyaimed to map the nucleotides contained in ahuman haploid reference genome (more thanthree billion).

Objective of the Human Genome Projectis to understand the genetic makeup of thehuman species, the project has also focusedon several other nonhuman organisms such asE. coli, the fruit fly, and the laboratory mouse.

Project identified and map theapproximately 20,000–25,000 genes of thehuman genome from both a physical andfunctional standpoint.

Number of bones ........................................ 206Number of muscles ..................................... 639Number of ribs .............................................. 24Number of bones in skull .............................. 22Number of bones in neck ............................... 7Number of bones in face ............................... 14Number of cranial nerves ...................... 12 pairsNumber of spinal nerves ....................... 31 pairsNumber of heart beat ........... 70-72 times/minuteRespiratory rate ................... 16-20 times/minute

Rate of blood pressure ........................... 120/80 mm. Hg.Number of RBC's ................. in male - 5,000,000/Cu. m.m.

in female - 45,000,000/Cu. m.m.Life span of RBC ............................................. 120 daysLife span of WBC ........................................... 2-15 daysAmount of blood ............................................. 5-6 litresAverage amount of haemoglobin .. 14-15 mg/100 ml bloodWeight of brain .................................................. 1.4 kg.

Numbers in Human Body

Mangosteens etc are includedin tropical fruits.

Silent valley is a conservedforest.

Tropical rain forest is seen inAssam.

Nicotine is a poisonousalkaloid present in Tobacco.

Brazil is the native place ofcashewnut.

Rainforests occur in WesternGhat and Eastern Himalayas.

‘Vanamahotsav’ started in1950.

Chipko movement isconnected with plantconservation.

Botanical survey of India

Test and DiseasesByopsi ....................................................... CancerLepromin Test .......................................... LeprosyEliza Test ....................................................... AidsWestern Blot ................................................. AidsShik Test ................................................. DiptheriaTuberculin Test ................................. TuberculosisPapsmear ......................................... Uterus CancerGlycocelated Haemoglobin ..................... DiabeticsE.E.G .............................................. Brain DiseasesE.C.G .............................................. Heart DiseasesMamography ....................................Breast CancerWidal Test ................................................ TyphoidVasarman Test ......................................... Syphilles

(BSI) with its head office in Kolkata came intoexistence in 1890.

National Botanical Garden (National BotanicalResearch Institute, NBRI) is situated in Lucknow.

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The Ramsar ConventionThe Ramsar Convention is an international treaty for the conserva-tion and sustainable utilisation of wetlands. Ramsar Convention(1971) was drafted at Ramsar, Iran. The headquarters is located inGland, Switzerland.

World Wetlands Day occurson 2 February each year.

Cloning Cloning is the process of

producing many identicalorganisms or clones (clonemeans exact carbon copy orcopies of a single parent).

It is the production of oneindividual organism from anucleus, cell or asexual offshotor another.

Ian Wilmut and his colleaguesat the Roslin Research Institutein Scotland cloned the firstsheep Dolly.

The young one of Dolly,named Polly, was born in 1998.

Ian Wilmut is considered as

the father of cloning. Carbon copy is the first cloned

cat, in 2001, at Texas A and Muniversity.

Cell cloning is based on theproperty of totipotency ( inplant) or pleuripotency ( inanimals).

Totipotency is a potentialability of plant cell to grow intocomplete plant. Pleuripotencyis the potential ability of ananimal cell to develop into anytype of cell in the animal body.

Species clonedTadpole, Carp, Mice, Sheep,Rhesus Monkey, Gaur, Cattle,Cat, Dog, Rat, Mule, Horse,Water Buffalo and Camel.

Tallest Animal ........................................................................... GiraffeLargest Bird ............................................................................ OstrichSmallest Bird................................................................. Humming BirdLargest snake ..................................................................... AnakondaLargest Mammal ............................................................. Blue WhalesLargest animal in land ............................................... African ElephantLongest flying bird ............................................................... ArticturnLargest Reptile .................................................................... CrocodileFastest animal........................................................................... Chetta

The Scientific NamesIndian elephant ............................. Elephas maximsFrog ......................................... Rana hexadactylaMan ................................................ Homo sapiensCat ............................................ Felix domesticusHornbill ....................................... Buseros bywrnisPeacock .......................................... Pavo cristatusTiger ............................................. Panthera tigrisCockroch ........................... Periplaneta americanaEarthworm ............................ Pheretima PosthumaCrow ......................................... Corvus SplendensParrot ....................................... Psittacula krameriPenguin .................................. Aptenodytes forsteriSparrow.................................... Passer domesticusWhale .................................. Balaenoptera indicaCow ..................................................... Bos indicaPig ...................................................... Sus scrofaCamel .................................. Camelus dromedariusHorse ............................................ Equus caballusDonkey ............................................ Equus asinusRabbit ................................ Oryctolagus cuniculasSqurrel ............................... Funambulus pennanti

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PHYSICS

Physics is the study of the proper-ties of matter and energy.

MOTION The length of the path be-

tween two points is the dis-tance between them.

Physical quantities that haveonly magnitude and nodirection are called scalarquantities.Eg: Distance, speed, time,work, mass, density, tempera-ture etc.

Physical quantities that haveboth magnitude and directionare called vector quantities.Eg: Displacement, weight,velocity, acceleration etc.

Speed is the distance travelledby a body in unit time. It is ascalar quantity. Its unit is m/s.

SpeedDistance

Time

Velocity is the displacementper unit time. It is a vectorquantity and its unit is m/s.

TimentDisplacemeVelocity

Acceleration is the rate ofchange of velocity. It is a vec-

tor quantity and its unit ism/s2.

A decrease in the velocity withtime is called deceleration orretardation. It is otherwiseknown as negative accelera-tion.• If the acceleration remainsconstant, i.e., it does notchange with time it is said tobe uniform acceleration.• The earth attracts every-body towards its centre. Theacceleration with which freelyfalling bodies are attractedtowards the earth is called theacceleration due to gravity. Itis same for all bodies and itsvalue is 9.81 m/s.

Inertia is the tendency of abody to continue in its stateof rest or the state of uniformmotion along a straight line.

Galileo discovered law of in-ertia.

An athlete run some distancebefore taking a long jump, byrunning the athlete gives him-self larger inertia of motion.

As the train starts moving, aman sitting inside leans back-wards because of inertia ofrest.

The branch of science whichdeals with the study of relativemovement of interactingsurfaces is called tribology.

In order to increase stability,a person climbing a hill bendsforward.

The flying of birds is a con-sequence of Newtons thirdlaw of motion.

Equations of Motion Three exists some relation be-

tween velocity accelerationand the time intervals duringwhich we study the motion ofa body. These relations arecalled equations of motion.They are:

V = u + atS = ut + 1/2 at2

2as = v2 – u2

where v - final velocityu - initial velocityt - time intervala - uniform accelerations - displacement

The force required to stop amoving body depends on itsmass and also on its velocity.

Momentum (P) is defined asthe product of mass and ve-locity of a body i.e, P = mv

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GRAVITATION The attractive force of earth,

or other celestial body, on anobject is called gravity.

The earth attracts everybodytowards its centre. Theacceleration with which thefreely falling bodies areattracted towards the earth iscalled the acceleration due togravity (g).

Value of g = 9.8 m/s2

The value of g at the centre ofearth is zero.

The value of g is very high atpolar region.

The value of g is very small atequitorial region.

The weight of a substance iszero at the centre of earth. Asthe mass of the substancesincreases the gravitationalforce between them alsoincreases.

The weight of a body inearth is very high in the polar

region and low in the equatorialregion.

The weight of a body on themoon will be less than itsweight on the earth. This is sobecause the mass of the moon

is 181 of the mass of the earth

its radius is1

3.66 of the radius

of the earth. Therefore, the ac-celeration due to gravity expe-rienced on the moon will be lessthan the acceleration due togravity experienced on the

earth. This will be about 16 g.

On the moon an astronaut can-not drink lemonade with thehelp of a straw because - Thereis no atmosphere on the moon.

Gravitation keeps the planets in orbit around the Sun.

Momentum is a vector quan-tity

Unit of momentum is Kg m/s.

FORCE Force is any influence that

tends to change the state ofrest or the uniform motion in astraight line of a body.

Unit of force is Newton The force of attraction bet-

ween like molecules is calledcohesion.

The force of attraction be-tween unlike molecules is

called adhesion. Weight can be defined as the

force with which earth attractsa body.

Weight, w = m × g Mass remains constant while

weight varies from place toplace.

Friction is a force that resiststhe movement of one surfaceover another.

The force required by a re-volving body is called centrip-

etal force. Friction can be reduced by

changing over from slidingto rolling

When a man circles round theearth in a spacecraft, his massremains constant but weightbecomes zero

Two object lossing the sameweight when immersed in wa-ter must have the same den-sity

Centrifugal force helps toseparate cream from milk.

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The mass of a body whichdetermines the gravitationalforce of attraction due to earthis called gravitational mass.

Escape velocity is the minimumspeed which a spacecraft musthave to escape from the earth'sgravitational force. It is7 miles/s. (or 11.2 km/s)

The escape velocity of a bodyis different and differentcelestial bodies.

In the absence of an effectiveforce of gravity, bodies becomeweightless in artificial satellites.

Gravitational field is the spacearound a massive body inwhich gravitational force ofattraction is felt.

Planets move slower alongtheir orbits when they arefarthest from the sun (atapogee) and they move fasteralong their orbits when theyare nearest to the sun (atperigee)

Gravitation is responsible forkeeping the Earth and the otherplanets in their orbits aroundthe Sun; for keeping the Moonin its orbit around the Earth;for the formation of tides; fornatural convection, by whichfluid flow occurs under theinfluence of a density gradientand gravity; for heating theinteriors of forming stars andplanets to very high tempera-tures; and for various otherphenomena observed onEarth.

The line on earth’s surfacepassing through the placeshaving zero dip is called themagnetic equator. It passesthrough Thumba.

VISCOSITY ANDSURFACE TENSION Capillary action is responsible

for the absorbance of water bythe plants and oils by the wickof lamps.

Fluids flow with zero viscosityis called superfluids (anti-gravity property).

The force within the liquidwhich opposes the relativemotion of one layer over theother is called viscosity.

Venturimeter is used for mea-suring the rate of flow of liq-uids.

Viscosity is the internal fluidfriction.

Surface tension is the propertypossessed by a liquid surfacewhereby they appear to becovered by a thin elasticmemberane.

Surface tensions is caused byunbalanced molecular cohe-sive force.Unit of surface tension is N/m.

When the temperature of fluidsincreases viscosity decreases.

The surface tension decreaseswith rise of temperature.

Surface tension is a propertyof a liquid by which the freesurface of a liquid behaves likea stretched elastic membrane,having contractive tendency.

The larger the surface, themore energy there is. Tominimize energy, most fluidsassume the shape with the

smallest surface area. The spherical shape of rain

drops and mist drops are dueto surface tension. Thespherical shape is attained tomaintain equilibrium.

Soap bubbles also tend to formthemselves into shapes withminimal surface area.

Soap is added to water toreduce the surface tension, soclothes (or whatever else) getmuch cleaner.

Water has a fairly low viscosity;things like shampoo or syruphave higher viscosities.

Viscosity also depends ontemperature : engine oil, forinstance, is much less viscousat high temperatures than it isin a cold engine in the middleof winter.

ELASTICITY Elasticity is the ability of a

body to return to its originalshape and size on the removalof the deforming force.

Glass is more elastic thansteel and steel is more elasticthan rubber.

If a body does not regain itsoriginal size and shape afterthe removal of deforming force,it is called a plastic body andthis property is called plasticity.Eg: Clay, Plasticine etc.

DENSITY &PRESSURE

VolumeMassDensity

waterofDensitybodyaofDensitydensitylative Re

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The amount of water vapourin the air is termed as humidity.

When a piece of ice floatingon the surface of water in abucket melts completely, thewater level will remain thesame.

An iron nail floats on mercurybut sinks in water because thespecific density of iron islower than that of mercury andhigher than that of water.

A petrol fire cannot beextinguished by throwingwater on it since the densityof water is more than thedensity of petrol, water sinksbelow the petrol when it ispoured over a petrol fire.

The density of sea water ishigher than the density ofriver water, therefore it iseasier to swim in the sea thanin river. This is why a shipentering from river mouth tosea rises up a little.

Ice floats on water because itsweight is less than the weightof an equal volume of water.

Ice floats on water but sinksin alcohol because the densityof alcohol is lower than thatof water.

The density of water is maxi-mum at 40C

The pressure at a point on asurface is the thrust actingnormally per unit area aroundthat point.

PascalormNArea

Thrustessure 2/Pr

The total normal force exertedby a fluid on a surface is calledthrust. Its unit is Newton (N).

Pressure increases with depth The pressure inside a baro-

meter remains high under acalm climate.

Mercury is used as the liquidin thermometers as it does notwet glass.

Pascal’s law states that pre-ssure in a fluid in equilibriumis the same everywhere.

Water distribution in cities,flush tank, hydraulic brake,hydraulic lift, hydraulic pressetc are working based onPascal’s law.

The lactometer used to testthe purity of milk is based onthe principle that the greaterdensity of a liquid, the lesserwill be the immension of anobject.

WORK, ENERGYAND POWER

Work refers to an activityinvolving a force andmovement in the directon of theforce. A force of 20 newtonspushing an object 5 meters inthe direction of the force does100 joules of work.

Energyis the capacity for doingwork. You must have energy

Eye Opener

When a bird sits on a very high voltage cable without having any

insulation cover on it, its feathers tends to spread out due to

electrostatic repulsive force. ie; feathers on either side of the bird

become charged of like nature. (either both become positively charged

or both become negatively charged).Hence repulsion takesplace.

to accomplish work - it is likethe "currency" for performingwork. To do 100 joules of work,you must expend 100 joules ofenergy.

Power is the rate of doing workor the rate of using energy,which are numerically thesame. If you do 100 joules ofwork in one second (using 100joules of energy), the power is100 watts.

Unit of energy is joule. The energy possessed by a

body due to its position in afield of force or configurationis called potential energy.

P.E = mghm = mass g = gravityh=height (distance betweenthe body and the surface)

Energy of a body due to itsmotion is called kinetic energy.

Kinetic energy = 12

2mv(m = mass, v = velocity)

The change in the kineticenergy of an object is equal tothe net work done on theobject.

Mechanical energy can beeither kinetic energy (energy ofmotion) or potential energy(stored energy of position).Objects have mechanical

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energy if they are in motionand/or if they are at someposition relative to a zeropotential energy position

Rate of doing work is calledpower. Its unit is watt

timeworkPower

Escape velocity is the velocitywith which a projectile must beprojected in order that it mayescape the earth’s gravitationalpull.

The escape velocity from thesurface of the earth is 11.2 kms

The escape velocity from theplanet, Jupiter is 61 km/second.For Mercury it is 42 km/second.

According to law ofconservation of energy ofAlbert Einstein, energy canneither be created nor bedestroyed but it may betransformed from one form toanother.

The energy possessed by thewater collected in the reser-voir of a dam is potential en-ergy

When a force acts upon anobject causes a displacementthen, it is said that work wasdone upon that object.

There are three key ingredi-ents to work - force, displace-ment, and cause.

The work done by a force ona body is defined as the prod-uct of the magnitude of theforce and the distance movedin the diection of force.

Work done = force × distance A boy, swinging a stone, tied

to a string, with a uniform

speed in a circle in a horizon-tal plane over his head, doesno work.

Unit of work is Newton metre(Nm).

LEVERS A lever is a simple machine

consisting of a rigid rod pivotedat a fixed point called thefulcrum. It is used for shiftingor raising a heavy load orapplying force in a similar way.

A body in which a force is feltis called resistance (R) and theforce applied here is calledeffort (E).

If the fulcrum comes inbetween resistance and effortsuch levers are called Ist orderlevers. Eg: balance, nail puller see-saw,a pair of scissors etc.

If resistance comes in betweeneffort and fulcrum then suchlevers are called IInd orderlevers. Eg: Wheel barrow, nut crackeretc.

If effort is between resistanceand fulcrum such levers arecalled III rd order levers.

Eg: Pincers, Icetongs etc. Efficiency of a machine

=PoweroutputPower input

Levers can be used to exert a large force overa small distance at one end by exerting only asmall force over a greater distance at the other.

Machanical advantage of a

machine =loadeffort

WAVES Electromagnetic waves are

coupled periodic electricaland magnetic disturbancescreated by oscillating electriccharges.

All waves of the electro mag-netic spectrum travel at thesame velocity, a quantityknown as the speed of light.The speed of light is approxi-mately 3×108 m/s (about186,000 miles per second).

Electromagnetic waves cantravel through vacuum.

Transverse wave is a type ofenergy wave in which motionof the particles is perpendicu-lar to the motion of the wave.

Wave on a rope and waves onthe surface of water are trans-verse.

If the motion of the particlesis along the direction of mo-tion of waves, it is called a lon-gitudinal wave.

Sound waves in a medium(solid, liquid or gas) are longi-tudinal.

Transverse waves travel inthe form of crests and troughswhile longitudinal wave trav-els in the form of compres-sions and rarefactions.

Earthquake waves are infra-sonic waves.

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The property which distin-guishes transverse wavesfrom longitudinal waves ispolarization.

Diffraction is the property inwaves of turning round theedges of an obstacle.

Sound can be heard around acorner due to diffraction.

When a wave strikes a surfaceof separation of two differentmedia, some of it is thrownback into the original medium.This property of bouncing ofthe waves is called reflection.

The property of sound reflec-tion is used by bats (whichcannot see in the dark) for fly-ing during night .

Visible light is electromagneticwave in the range of frequen-cies 4.3×1014 to 7×1014 Hz.Electromagnetic waves do notrequire any material mediumfor their propagation, theycan travel in vacuum.

RADAR is the abbreviation ofRadio detection and ranging.

SOUND Sound is a travelling wave. Sound requires medium to

travel. Sound cannot travel through

vacuum. Study of sound is known as

Acoustics. Echo and reverberation are

due to the reflection of sound.For the production of echothere should be a minimumdistance of 17m between usand the reflecting surface.

Bats can fly in the darkbecause they can generateultrasonic sound and if thereis any hindrance in their way

the sound waves get reflectedand they can change theirdirection. They use thismethod to catch insects also.

Since sound waves need amedium to travel they cannotbe transmitted throughvacuum.

The audible frequency ofhuman ear is between 20 hertzand 20,000 hertz (20 KHz).

A speed greater than thespeed of sound is referred toas supersonic.

Velocity of sound in the air is340 m/s.

Sound consists of waves ofalternate compression andrarefaction that transmit ki-netic energy through a me-dium.

Frequency of a sound waveis the number of wave-lengths (vibrations) that arecompleted in a given periodof time.

Doppler effect is the changein a sound wave’s frequency(and wavelength) that iscaused when the hearer andsound source move relativeto each other.

Sounds are distinguishedfrom each other by pitch (fre-quency), loudness (inten-sity) and quality.

We can recogn ise ourfriends from their voices dueto the quality of sound.

Phonogram is a machine toreproduce sound.

The speed of sound de-pends on the medium thewaves pass through.

Sounds with frequencieslower than the lowest limitof human hearing (about 20

Hz) are called infrasonicwaves.

Sounds of frequency higherthan 20,000 Hz are known asultrasonic and are inaudiable.

SONAR stands for SoundNavigation And Ranging. Ituses ultrasonic waves.

Sound travels faster throu-gh solids, expecially, throu-gh metals.

The intensity of sound ismeasured in decibel.

The intensity of polite con-versation is 40 db-30 db.

During night the allowed in-tensity of sound in a hospitalarea is 40 db.

The reverberation of sound ina hall results due to continuedreflection

Sound travels faster in steel Sound can travel only

through a medium. It cannottravel through vacuum. It trav-els through solids, liquids andgases.

Equipment for generating orusing sound includes musicalinstruments, hearing aids,sonar systems and soundreproduction and broadcasting equipment. Many ofthese use electro-acoustictransducers such asmicrophones and loudspeakers.

How do bats fly atnight?

Bats can fly in the darkbecause ultrasonic wavesproduced by them during flying arereflected back to them from theobstacles in their way and hencethey can fly with out difficulty.

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LIGHT ‘The corpuscular theory’

related to light was proposedby Issac Newton in 1675.

Study of light is known as op-tics.

Light an electromagnetic radia-tion.

Through vacuum electromagnetic waves travels with aspeed of 2.9979×108 m/s.

Paper, cardboard and stone areexamples for opaque substa-nces (substance which do notpassess light).

Substances which allow thelight to pass through are calledtransparent substances.Eg: glass

The particle which is sup-posed to travel faster than lightis tachyon

Tachyons were discovered byE.C.G. Sudarshan.

On a rainy afternoon a rainbowis seen in the east

A rainbow is always seen in theopposite direction of the sun.

Rainbow is caused by reflec-tion, refraction and dispersionof light by the water particlespresent in the atmosphere.

LASER is Light Amplificationby Stimulated Emission of Ra-diation.

Laser is the surface intense ra-diation.

LASER is a source of intensemonochromatic light in the ul-traviolet, visible or infrared re-gion of the spectrum.

LASER beams are used in themedical field to perform minuteoperations.

LASER was discovered byTheodore Maiman in 1960.

Visible spectrum is the bandof colours obtained when a rayof light passes through aprism.

Spectrum consists of sevencolours viz Violet, Indigo, Blue,Green, Yellow, Orange and Red(VIBGYOR).

Violet light is scattered most,blue somewhat less, and green,yellow and orange still less, inthat order.

Red light is scattered least. The beautiful colour of the

soap foam and oilspread wateris due to interference of light.

Red, green and blue are theprimary colours.

Green objects placed in redlight will appear black.

In the spectrum violet light hasshort wave length and high fre-quency. While red light hasthe highest wave length andthe least frequency.

A diamond sparkles due to to-tal internal reflection becauseit has a high refractive index.

Scattering of light is respon-sible for sky being seen asblue. This is because blue andviolet colour have short wavelength and hence scatter more.

MASER is Microwave Ampli-fication by Stimulated Emis-sion of Radiation. It was dis-covered by Charles H. Towns.

Refraction is the sudden

change of direction of lightwhen passing from onetransparent substance toanother. When we put a stickin water it seems to be bended.It is due to refraction.

Diffraction is the spreading outof waves of light as it passesthrough a narrow aperture.The spreading of light raystowards the screen from aprojector in film theatre is dueto diffraction.

Dispersion is the splitting upof light ray into differentcolours. Rainbow is formeddue to dispersion. The sevencolours of light has differentwavelength. Hence when lightpasses through a prism eachcolour gets refracted atdifferent angles.

A bubble of water shines be-cause of total internal reflec-tion.

Refraction of light through airhaving very large temperaturegradients causes a mirage.

A periscope is a device whichworks by the principle of re-flection and refraction.

When there is thunder we seethe lightning first and hear thethunder later because the ve-locity of light is greater thanthe velocity of sound.

James Clark Maxwellfounded that lights areelectromagnetic waves.

Wave theory of light was dis-covered by ChristianHuygens.

Microwave Amplification byStimulated Emission of Radia-tion was discovered by CharlesH. Towns.

Eye Openes:If two bulbs of power 40w and100w are joined in series andconnected to the domesticelectric supply terminals, the40w bulb glows much morebrighter than the 100w bulb.

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The term light year is a unitemployed in measuring Dis-tance.

The rays which appears tooriginate outside the earth -The cosmic rays

In a Doctor’s stethescope thesound is intensified because ofreflection of sound

Light from the sun reaches theearth in 8 minutes.

Light travels fastest throughvacuum. Through vacuumlight travels with a speed of3×108m/s.

The shortest distance for clearvision is 25 cm.

Myopia or short sightednessis such a type of defect inwhich one can see nearby ob-jects clearly but is difficult tosee objects at long distances.Here image of the substancefalls in front of the retina.

Myopia can be corrected byusing a concave lens.

Hypermetropia or longsightedness is such a type ofdefect in which one can seedistant objects clearly whereasnearby objects look blurred.Here the image of the sub-stance falls behind the retina.

Hypermetropia can be cor-rected by using aconvex lens of appropriate fo-cal length.

Persons suffering from bothmyopia and hypermetropiause bifocal lenses to with-stand the condition.

Astigmatism: This defect isdue to the cornea not beingspherical. This defect can becorrected by using a cylindri-

cal lens, instead of a sphericallens.

As the age advances, theelasticity of eye becomes verymuch reduced. As a result thenear point of eye recedesgradually resulting in pres-byopia. It can be corrected byconvex glasses.

When we observe distantobjects, the focal length of theeye lens increases and if weobserve the objects near by,the focal length of eye lensdecreases.

Twenty - Twenty means per-fect vision.

The image formed on the retina ofthe human eye is real and in-verted.

The lens in the human eye inconvex.

Pigments are substances usedto colour paints, filters, plas-tics and other materials.

The sky generally looks bluebecause the blue colour ofshort wave length is scatteredmore than the longer waves ofred light.

It is true that the violet wavesare dispersed, even more thanthe blue. However, the skydoes not appear violet be-cause the sunlight is relativelyweak in violet light.

Red colour has the longestwavelength and shortestfrequency whereas violetcolour has the highestfrequency and shortest wavelength.

The formation of brilliantcolours in soap film is a conse-

quence of the phenomenon ofmultiple refraction and inter-ference

An astronaut on an earth sat-ellite will observe the sky asBlack.

The shortest height of a planemirror required to show the fullsize image of a person of height

‘L’ cm is L2

cm .

Dioptre is the unit of power oflenses.

Concave mirror is used as aburning glass.

For the rear view, motorists useconvex mirror.

To concentrate light on theteeth, the dentists use concavemirrors.

Film is a part of the camerawhich is analogous to theretina in the human eye.

HEAT AND THER-MODYNAMICS

Absolute zero is the lowestpossible temperature which isequal to 0K or -273.16°C or -459.69°F.

Temperature is the degree ofhotness and heat is a form ofenergy which increases thetemperature of a body.

Specific heat capacity of asubstance is the amount ofheat required to raise the tem-perature of the substancethrough 1°C

As we go up in the atmo-sphere, the temperature de-creases.

Plasma is the fourth state ofmatter. Solid, liquid and gas areother three states of matter.

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A black surface absorbs heatmore than other colours.

Cryogenics is concerned withthe production, control andapplication of extremely lowtemperatures.

At ultra high temperature mat-ter exist in plasma form 99%of matter in the Universe is inplasma form.

One calorie is the amount ofheat needed to raise the tem-perature of 1gm of water by1oC.

Steam causes more severeburns than water of the sametemperature because steampossess more heat energy dueto latent heat than water.

Transmission of heat fromone point to another withoutheating the medium is calledradiation.

Cotton dresses are safe forwearing while cooking.

Conduction is the process ofnet energy transfer through asubstance without the move-ment of the substance itself,but by molecular collisions.

Very poor conductor, such asglass are called Insulators. Airis a good insulator.

Mica is a good conductor ofheat, but a bad conductor ofelectricity.

Perspiration is maximum, whentemperature is high and air ishumid.

Evaporation takes place at alltemperatures and is accompa-nied by cooling.

Melting point of ice can beraised by the decrease of pres-sure.

Water has maximum density at4o C. Water expands when itfreezes.Water occupies maxi-mum volume at 0oC.

The Clinical Thermometer isspecially designed to measurehuman body temperature.Normal human body tempera-ture is 36.90 C (or 98.4°F)

Melting point of mercury is -39°C and that of alcohol is -115°C.

The main source of energy inthe biosphere is solar energywhich reach earth by means ofradiation.

Water expands on freezing.Due to this reason when wa-ter is filled in a bottle and isallowed to freeze the bottlebreaks, and during winter wa-ter pipes break in cold re-gions.

MAGNETISM ‘Lodestones’, are natural mag-

nets. Magnetic lines of force cannot

penetrate certain materials aseasily as they can penetrate airor vacuum. Such materials arecalled “diamagnetic.’’

Diamagnetic materials havenegative susceptibility.

Bismuth, antimony, zinc, silver,copper, gold, lead, water, al-cohol, hydrogen and the in-ert gases are diamagnetic.

The law of magnetic polesstates that like poles repel, un-like poles attract.

A freely suspended magnetstands vertical at magneticsouth pole

“Ferromagnetic’’ sub-stances are those which canbe magnetised to a great ex-tent.

Iron steel, nickel ,cobalt,alloysof these substances, and ga-dolinium are ferromagneticsubstances.

Paramagnetic materials havefeeble magnetic properties.Platinum , solutions of saltsof iron, oxygen, manganese,palladium, osmium etc are ex-amples of paramagnetic sub-stances.

Inside a magnet, direction ofmagnetic lines of force is fromsouth to north.

Tesla is the unit of strengthof magnetic field.

The instruments which aredependent of magnetic powerof electricity are fan, tele-phone receiver, Dynamo etc.

ELECTRICITY Laws of electrolysis were for-

mulated by Michael Faraday(Father of electricity).

Electric fittings are earthedbecause in case of a short cir-cuit, the current passes to theearth to overcome the dam-ages.

Filtered water at normal tem-perature is better conductor ofelectricity than filtered hotwater and distilled water.

Conductors are substancesthat allow electric charges toflow through it .

EclipseLunar eclipse occurs when theearth comes between the sunand the moon. While solareclipe occurs when the mooncomes between the sun and theearth.

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Metals and graphite are goodconductors of electricity.

Silver is the metal havinglowest resistance.

The best conductor of elec-tricity is silver.

Free electrons constitute cur-rent in a conductor.

Insulators do not allow currentto flow through it .

Current through a conductoris the flow of electronsthrough it.

Rubber, plastic, paper, glass,mica etc are insulators.

Elements such as silicon andgermanium allow feeble cur-rents to pass through themand they are known as semi-conductors.

Air without moisture (dry air)is an insulator.

The unit of electric charge isColoumb. It is equal to thecharge of 6.25×1018 electrons.

TimeeChCurrent arg

A high current is produced ina low resistance circuit whentwo wires of main comes incontact with each other. Thisis called short circuiting.

Electric bulbs are filled withgases like argon, neon,nitrogen etc.

When an isolated conductingsphere is given a positivecharge, its mass decreases.This is because, ‘givingpositive change’means‘taking electrons out of it’.

The principle on which quartzcrystal in watch works is peizoelectricity. Peizo electricity isthe property of some crystalsto develop an electromotive

force or voltage across oppo-site forces when subjected toa mechanical strain and con-versely, to expand or contractin size when subjected to anelectromotive force.

220-230 volt is the voltage atwhich the alternate current(a.c) is supplied for household use in India.

The frequency of householda.c in India is 50 hertz.

An inductor is a device whichpasses dc but blocks ac.

Alternating current is usedmore widely than Direct Cur-rent.

ac (alternating current) is moredangerous than dc (direct cur-rent).

Usually the air inside an elec-tric bulb is removed becausewhen the filament (tungsten) isheated in the presence of air, itforms oxide by combining withoxygen present in the air andreadily gets fused.

Nichrome is used as a heatingelement in many appliance be-cause it has high resistivity andit resists oxidation in air whenred hot.

An electric bulb makes a bangwhen it is broken because thereis a vacuum inside the electricbulb. When the bulb is bro-ken air rushes in at a greatspeed from all sides to fill thevacuum and this produces thesound.

To avoid overloading, a de-vice called a ‘fuse’ is insertedin series with the circuit.

The fuse is a piece of wiremade of financial Lead.

The fuse offers a great deal of

resistance to the electric currentand melts at a fairly low tem-perature. The fuse wire musthave a low melting point.

A fuse wire is used to preventan unduly high electric cur-rent to pass through a circuit.

Capacitor is a device used tostore electrical energy but itis not a device to store elec-tric charge.

The emf or potential differencemeasured in volt is called volt-age.

A convenient unit to measureelectric power is the kilowatthour (kwh). This is often sim-ply called a unit.

1 kwh = 1000 watt x 3600 sec-onds

In our houses, electric wiringis done in parallel connectionso that all instruments in thehouse could get equal supplyof electricity.

when two cells of e.m.f‘V’volts each are connectedin series the effective emf isV+V=2Vvolts

Conductors Insulatorssilver glasscopper rubbergold oilaluminum asphaltiron fibre glasssteel porcelainbrass ceramicbronze quartzmercury (dry) cottongraphite (dry) paperdirty water (dry) woodconcrete plastic, air,

diamond,pure water

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When one cell is reversed ,theeffective emf is V-V=0 volts,ie, zero volts.

In parallel connection ofequal emf cells,whatever bethe number of cells used theeffective emf will be equal tothe emf of a single cell.

When we want a stronger cur-rent for a longer time parallelconnection is used.

A source of emf containingtwo or more cells is called abattery.

In a dry cell the negativeelectrode(cathode) is zinc andpositive electrode(anode) iscarbon rod.

The emf of a voltaic cell is1volt.

The emf of a dry cell is 1.5volts.

Colour of the light of sodiumvapour lamp is yellow.

Colour of the light of chlorinevapour lamp is green.

Light of nitrogen vapour lampis red.

Light of mercury vapour lampis white.

Light of neon vapour lamp isorange red.

Light of hydrogen vapourlamp is blue.

In our houses we get 220Vac.The value 220 representseffective voltage

The advantage of ac over dcis that it can be transmittedover long distances with mini-mum power loss

Resistance of carbon decreases with increase of tempera-ture.

In an electrical circuit a fuse

is connected in the live wireAlong with fluorescent tubesare fitted with a choke. Herethe choke coil steps up theline voltage.

An electrical appliance isearthed to prevent shock

One should not connect anumber of electrical appli-ances to the same powersocket because this can dam-age the domestic wiring dueto over heating

A capacitor (condenser) isused to store electric charge

"Hydro Power" is the termused for electricity producedthrough water

Electricity for domestic pur-pose is measured in kWh

The power of ordinary torchcell is 1.5 volt.

In the rechargable batteriesused in touch light, electric-shavers etc. nickel and cad-mium are used as electrodes.

ELECTRONICS Electronics is the study of

nature, control and applica-tion of electrons.

Modem is Modulator De-modulator.

Rectifiers are used to convertAlternating Current (AC) toDirect Current (DC).

An electronic oscillator is adevice which converts DCenergy into AC energy.

Silicon is used in solar cells. Materials whose resistivity

lies in between conductorsand insulators are called semiconductors.

Germanium, silicon, carbonetc are semi conductors.

A transistor transfers a sig-nal from a low resistance tohigh resistance .

The word transistor camefrom the process of transferand the resistor.

ELINT is electronic intelli-gence.

Triode was invented by LeeDe Forest.

IC chip is a circuit whichperforms the functions oftransistors, diodes, resistors,condensers etc altogether.

The largest IC chip manu-facturing company in theworld is INTEL.

Electrons are carr iers ofcurrent in a npn transistor.Holes are the carriers ofcurrent in a pnp transistor.

The frequencies transmittedby a TV station is calledchannel.

Soft X-rays are X-rays havinghigh wavelength and lowenergy. As these are absorbedby body tissues they are notused in taking photographs ofinternal organs.

X-rays having shortwavelength but high energyare called hard X-rays. Theseare used in the photographyof internal organs.

In order to study internalatomic structure of crystals,we use X-rays

“IC” chips for computers areusually made of Silicon

The process which makes thecurrent to pass in the samedirection is called rectification

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TELECOMMUNI-CATION

A revolution in wireless tele-communications began in thefirst decade of the 20th cen-tury, with Guglielmo Marconiwinning the Nobel Prize inPhysics in 1909 for his pio-neering developments in wire-less radio communications.

The first commercial electricaltelegraph was constructed bySir Charles Wheatstone andSir William Fothergill Cooke,and its use began on 1839.

Optical fibre provides cheaperbandwidth for long distance

communication

NUCLEAR PHYSICS A Geiger Counter or Geiger -

Muller Counter is used for de-tecting and measuring radia-tion.

Radio-Carbon Dating or Car-bon dating, widely employed todetermine the age of fossils ofanimals or plants. The radio-iso-tope carbon-14 is used in Car-bon dating process.

Chain reaction is a self sus-taining series of nuclear fis-sions, each one started by

Samuel MorseSamuel Finley Breese

Morse was an Americancontributor to the invention

of a single-wire telegraphsystem based on Europeantelegraphs, co-inventor of

the Morse code.

The Nobel Prize inPhysics 2010

The Nobel Prize in Physics 2010was awarded jointly to Russianborn scientists, Andre Geim andKonstantin Novoselov “for groundbreaking experiments regardingthe two dimensional materialgraphene”, a super-thin andstrong form of carbon with highconductivity that can be used fortouch screens and light panels.

In 1901, Guglielmo Marconiestablished wireless communi-cation between St. John's,Newfoundland and Poldhu,Cornwall (England), earninghim the Nobel Prize in Phys-ics for 1909

Alexander Graham Bell in-vented the telephone.

The first commercial tele-phone services were set up in1878 and 1879 on both sidesof the Atlantic.

Telex means Teleprinter Ex-change.

INTELSAT (InternationalTelecommunication SatelliteOrganisation), with its head-quarters in Washington DC,was established on February12, 1973. It operates spaceequipment and earth stationsowned by telecommunicationentities in each country.INTELSAT’S 13 satellite sys-tem provides about two-thirds of the world’s interna-tional telecommunication ser-vices to more than 140 coun-tries including India.

Father of cybernetics -Norbert Weiner

RADAR is Radio Detectionand Ranging.

RADAR is a device that usesradio waves to detect the po-sition of objects such asaeroplanes, missiles etc.

Radar was invented by Albert H.Taylor and Leo C. Young.

The first telecommunicationsdevice was the telegraph.

A television camera takes 25 or30 electronic photographs(called frames) of a scene ev-ery second.

Hybrid computers are a com-bination of the analog anddigital computers.

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neutrons emitted in a previ-ous fission.

Proton was discovered byRutherford.

Electron was discovered byJ.J.Thomson.

James Chadwick discovers theneutron.

Out of the three radiations -alpha, beta, and gamma,gamma radiation is most pen-etrating.

Enriched uranium is uraniumwith more of the isotope ofUranium - 235.

The age of rocks may be cal-culated through radioactivedating using uranium iso-topes.

Alpha particles () are posi-tively charged. Basically rays are Helium nuclei.

Gamma rays are electromag-netic radiation emitted by thenuclei of radioactive ele-ments.

A tracer is minute amount ofa radioisotope, added to alarge amount of non-radioac-tive isotopes of elements.

Half-life is the time taken forhalf of any amount of a radio-active isotope to decay.

Radiocarbon 'carbon - 14'has a half-life of 5,730 years.

Isotopes used in dating rocksinclude Uranium-235 whichbecomes lead-207; thorium-

232 which becomes lead-208;rubidium-87 which changesinto strontium-87; and potas-sium-40 which changes intoargon-40.

Nuclear fusion is also knownas thermo-nuclear reactionbecause it demands extremelyhigh temperatures.

A breeder reactor is that whichproduces more fissionablematerial than it burns.

The enormous energy re-leased in an atomic explosionis due to the conversion ofmass into energy.

Neutron is used to trigger-offthe nuclear fission reaction.

Atom bomb is an example ofnuclear fission reaction, whileHydrogen bomb is that ofnuclear fusion reaction.

More energy is produced in afusion reaction than fissionreaction.

The monozite found abunda-ntly in coastal areas of Keralacontains thorium.

The temperature required forthe maintenance of fusion isabout 350000000°C.

ATOMICREACTORS

Nuclear power is the fourth-largest source of electricity inIndia after thermal, hydro andrenewable sources of elec-tricity.

In 2010, India has 19 nuclearpower plants in operationgenerating 4,560 MW while 4other are under construction.

The first atomic reactor in In-dia is 'Apsara' in Trombay(Maharashtra)

Nuclear Fusionand Fission

The process of formation of a heavily weighed

nucleus by the fusion of two or more low weighed

nucleus is called nuclear fusion. On earth, the most likely

fusion reaction is Deuterium–Tritium reaction. Deuterium and

Tritium are both isotopes of hydrogen. The splitting of nucleus of

an atom into two pieces having equal weight is called nuclear

fission. Otto Hahn in 1939 discovered nuclear fission. Nuclear

fission is the splitting of a massive nucleus into photons in the

form of gamma rays, free neutrons, and other subatomic

particles. The main difference between these two

processes is that fission is the splitting of an

atom into two or more smaller ones

while fusion is the

Power Plant Location StateNarora Atomic Power Station Narora Uttar PradeshRajasthan Atomic Power Station Rawatbhata RajasthanTarapur Atomic Power Station Tarapur MaharashtraKakrapar Atomic Power Station Kakrapar GujaratKudankulam Nuclear Power Plant Kudankulam TamilnaduMadras Atomic Power Station Kalpakkam TamilnaduKaiga Nuclear Power Plant Kaiga Karnataka

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India's first breeder reactor isset up at the place known asKalpakkam in Tamil Nadu.

The early reactors wereknown as Atomic Piles.

Heavy water, graphite andneutrons are used as modera-tor in nuclear reactors.

Coolant is a fluid used innuclear reactors to remove theheat produced in the core.

The coolant used in fastbreeder reactors is generallyliquid sodium.

Heavy water is used as a cool-ant as well as a moderatorfor nuclear reactors.

The moderator in a nuclearreactor slows down the fastmoving neutrons.

The commonly used modera-tors are graphite, heavy waterand berilium.

The main source of solar en-ergy is nuclear fusion.

The fast breeder reactor getsits name from the fact that itutilizes excess free neutronsto breed new fissionable ma-terial.

The original fuel in the fastbreeder reactor is plutoniumand uranium oxides or car-bides.

Cadmium rod is used in a re-actor to absorb neutrons.

Willers Frank Liby discov-ered carbon dating.

Coal is the most important rawmaterial for thermal powerplant.

Flyash is a waste product ofthermal power plants.

Cobalt-60 is commonly usedin radio therapy because itemits beta rays which hasmore energy than the X-rays.

SPACE PHYSICS

Space exploration began withthe launching of Russia’sSputnik-1 into space onOctober 4, 1957.

Sputnik-2 carr ied a dog‘Laika’to space.

The U.S.A. entered the spacearena on January 31, 1958 withthe launching of the Explorer-1.This satellite is credited withmaking the importantdiscovery of the Van Allenradiation belts around theearth, where electrons andprotons from the sun aretrapped by earth’s magneticfield.

The extremely large distancesbetween the various heavenlybodies like the stars andplanets can be expressed interms of two units namely lightyear and parsec.

One light year is the distance

travelled by light in one yearthrough space.

1 light year = 9.46×10 12

Kilometres 1 Parsec = 3.26 light years A galaxy is a vast collection of

billions of stars, dust andhydrogen gas isolated in spacefrom similar systems.

Galaxies are the buildingblocks of the universe.

The sun and the eight planetsbelong to the milky way galaxy,whose Indian name is Akash-Ganga.

Milky way is a spiral shapedgalaxy. There are nearly 1011

stars in the galaxy. Among numerous dim stars in

the sky, there are some groupsof bright stars. These groupsof stars stars. These groupsof stars forms certain shapesor patterns and are calledconstellations. The conste-llations were given the nameof the figures they resembled.

There are 89 constellations.The largest of these is Hydra,which contains at least 68 starsvisible to the naked eye.

A satellite is a heavenly bodythat rotates around a planet.

Venus is the brightest objectin the night sky, leaving out themoon. It is visible either in theearly morning in the easternsky or in the early evening inthe western sky and is called“morning star” and “eveningstar”.

Sun is our nearest star. It is ahot sphere of gas - 74%hydrogen, 25% helium and 1%other elements.

The sun is at a distance of 8

NPCILNuclear Power Corporationof India Limited is a PublicSector Enterprise under theadministrative control of theDepartment of Atomic Energy(DAE), Government of India.The main objective of NPCIis operating the atomic powerstations and implementingthe atomic power projects forgeneration of electricity

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light minutes from the earth. ie,it takes about 8 minutes forlight to travel from the sun tothe earth.

An asteroid is an irregular,rocky hunk, small both in sizeand in mass compared to aplannet.

In the belt which lies betweenMars and Jupiter there arethousands of minor planets orasteroids.

Ceres is the largest knownasteroid.

Meteor is the streak of lightobserved in the sky. They areformed when a particle ofmatter enters the earth’satmosphere and becomeincandescent as a result offr iction with atmosphericatoms and molecules. Meteorare also called shooting stars.

Stars twinkle because ofrefraction of light.

The tail of a comet points awayfrom the sun. This is due toradiation pressure.

The colour of a star is anindication of its temperature.

The plannet that has got a welldeveloped set of rings issaturn.

India’s satellite launchingstation is situated at Srihari-kota.

When a person is orbiting in asatellite, his weight becomeszero.

The ink of the pen leaks out inan aeroplane because pressureof ink inside is more than theambient pressure.

The Space Application Centrefor training in Satellite

Communication Technology islocated at Ahmedabad.

The credit for starting spacescience research in India goesto Vikram Sarabhai.

Moon has no atmospherebecause its gravity is notsufficient for any atmosphereto held on to it.

All stars have idential chemi-cal composition but they differin surface temperatures. Thisis the reason for the differencein spectra of stars.

The outward stream of protonsand electrons on the surfacethe sun during solar flares andsun-spot activity constitutethe solar wind.

UNITS ANDMEASUREMENTS

The purest form of gold is 24carats. Ornaments are usuallymade of 22 carat gold. Onemetric carat is equal to 200milligram.

The weight of preciousgems are also measuredin carat.

One gallon is equal to 4.546litres.

One horse power is equal to 746watts.

Light year is a unit of distanceused in astronomy.

Light year is the distance that

light travels in one year at thespeed of 3,00,000 km/sec.

Astronomical Unit is anotherunit of distance in space. It isthe mean distance betweenearth and Sun. One light yearcontains nearly 63282 Astro-nomical Units.

Par sec (Parallactic second) isyet another unit of distance inspace. One par second is equalto 3.08x1016m.

Lambert is the unit of inten-sity of light.

Pascal is the unit of pressure. Angstrom is the unit of the

wave length of light. Poise is the unit of viscosity

of fluid. Curie and Rutherford are unit

of radio activity. Unit of Plane angle is radian Unit of solid angle is steradian Newton is the unit of force Joule is the unit of energy and

work Unit of power is watt Hertz is the unit of frequency Coulomb is the unit of electric

charge Unit of electric capacitance is

farad Ohm is the unit of electric re-

sistance Becquerel is the unit of radio

activity Henry is the unit of inductance

Several systems of unit have been in use for describing measurement.The common systems are the C.G.S. system (centimeter, gram, second);the F.P.S. system (foot, pound, second) which is the British system, the

MKS system (meter, kilogram & second) and now internationallyaccepted is the System International Units, abbreviated as S.I. units.

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Weber is the unit of magneticflux

Lumen is the unit of luminousflux

Lux is the unit of illuminance Unit of electric conductance

is Siemens Joule is the unit of work. Dyne is the unit of force. Newton is yet another unit of

force. One newton = 10

5 dynes

Centigrade, Fahrenheit arethe units of temperature.

Degree is the unit of angle. Mho is the unit of conduc-

tance. Fathom is the unit of depth of

the sea. One fathom is equalto 6 feet.

In India, National PhysicalLaboratory of NewDelhi is re-sponsible for the maintenanceand improvement of physicalstandards of length and time.

Solar day is the period be-tween noons of two consecu-tive days.

BRANCHES OFSCIENCE

ActinologyA branch of science whichdeals with the chemical effectsof electromagnetic radiation.

AerodynamicsThe study of the motion andcontrol of solid bodies (eg. aircraft, rockets, missiles etc) inair.

AeronauticsA branch of science whichdeals with flight through air.

Austro physicsThe branch of physics con-

Quantity UnitLength .......................................................................... Metre (m)Mass ...................................................................... Kilogram (kg)Time ........................................................................... Second (s)Electric Charge .......................................................... Ampere (A)Temperature ................................................................. Kelvin (K)Frequency.................................................................... Hertz (Hz)Force, Weight ............................................................. Newton (N)Work, Heat .......................................................................... JoulePower, Radiant flux ........................................................ Watt (W)Pressure, Stress ........................................................... Pascal (Pa)Electric charge or flux ..................................................... Coulomb (C)Electrical potential difference, Electromotive force (emf) ..... Volt (V)Electric resistance, ................................................................ OhmElectric capacitance ........................................................ Farad (F)Magnetic flux ............................................................ Weber (Wb)Magnetic flux density, magnetic induction ....................... Tesla (T)Inductance ................................................................... Henry (H)Electrical conductance ..................................................... SiemensRadioactivity......................................................... Becquerel (Bq)Catalytic activity ................................................................. KatalThermodynamic temperature .................................. Degree CelsiusDerived UnitsArea ................................................................. square metre (m2)Volume ....................................................................... cubic metreSpeed, velocity........................................ metre per second (m·s-1)Acceleration ................................. metre per second squared(m/s2)Jerk ............................................... metre per second cubed (m·s-3)Angular velocity .............................................. radian per secondMomentum.................................................. Newton second (N·s)Torque, moment of force ......................................... Newton metreWavenumber ...................................................... Reciprocal metredensity, mass density ................. kilogram per cubic metre (kg·m-3)specific volume ....................................... cubic metre per kilogramentropy ...................................................... joule per kelvin (J·K-1)electric field strength ............................................... volt per metremagnetic field strength ....................................... ampere per metremolar energy .......................................................... joule per molespecific energy .................................................. joule per kilogramenergy density ............................................. joule per cubic metresurface tension .................................................. newton per metrethermal conductivity..................................... watt per metre kelvindynamic viscosity .................................................. pascal secondelectric charge density ............................ coulomb per cubic metreelectric current density ............................ ampere per square metreradian ..................................................................................... radsteridan ................................................................................. rad2

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Deputy Collector Rank File

cerned with the physical prop-erties of celestial bodies andthe interaction between mat-ter and energy with them.

AstronauticsThe scientific study of traveloutside the Earth’s atmo-sphere.

AudiologyThe science of hearing

BallisticsThe study of path (motion) ofprojectiles.

CosmologyThe science of the nature, ori-gin and history of the uni-verse.

CrystallographyThe study of structure ofcrystals.

DynamicsThe study of the behaviour ofbodies under the action of

which deals with effect ofmotion without reference tomass or force.

OpticsIt is the branch of physicsdealing with the study of light.

RheologyThe study of the deformationand flow of matter.

Solid state PhysicsThe branch of physics whichdeals with the nature and prop-erties of matter in the solidstate.

Statistical MechanicsThe study of the mechanicalproperties of large assembliesof particles or components interms of statistics.

TribogyThe study of friction and lu-brication.

forces which change theirmotion.

ElectronicsA branch of science dealingwith the study and develop-ment of circuit involving ther-mionic values, semi conduc-tors and other electrical com-ponents like resistance, ca-pacitors, inductances etc.

ElectrostaticsThe study of the effects as-sociated with electric chargeat rest.

FluidicsThe study and use of fluidflow through pipes in an analo-gous way to the flow of elec-tric current through circuits.

HolographyScience of recording three di-mensional image of an object.

KinematicsThe branch of mechanics

Galileo Galilei ........ Discovered the phases of Venus,the four satellites of Jupiter Io, Europa,

Callisto, and GanymedeChristiaan Huygens ............................ Wave theorySir Isaac Newton ............. Newton's Laws of Motion,

Universal gravitation, CalculusBenjamin Franklin ......... Discovered the two electric charges, 'positive' and 'negative'.James Watt ........... Modern condenser steam engineMichael Faraday ............ Electro magnetic inductionSir Chandrasekhara Raman ..... Scattering of light and

found the Raman effectNikola Tesla ............................... Alternating currentDaniel Gabriel Fahrenheit .................. Determined the

temperature scale called Fahrenheit scaleChristian Doppler ............................. Doppler effectJames Chadwick ......................................... neutronJ. Robert Oppenheimer ......................... Atom BombDalton ............................................. Atomic TheoryCarrier .......................................... Air ConditioningEvangelista Torricelli ............................... Barometer

Famous scientists and invention

Alessandro Volta .......................... Battery (Electric)Kirkpatrick Macmillan .................................. BicycleTennant ...................................... Bleaching PowderEdwin T. Holmes ................................ Burglar AlarmJohn Harrison ..................................... ChronometerNicolas & Jean Lumiere ................................ CinemaWilmut ...................................... Cloning, (Mammal)Rudolf Diesel .................................... Diesel EngineThomas Alva Edison ...........................Electric LampHenry W. Seely ................................... Electric Iron J.J.Thomson. ............................................ ElectronLewis E. Waterman .............................Fountain PenThomas Alva Edison ........................... GramophoneDenis Gason .......................................... HolographEdward Teller ................................. Hydrogen BombSir Frank Whittle .................................... Jet EngineTheodore Maiman ......................................... LaserElisha G. Otis ................................ Lift (Mechanical)Benjamin Franklin ..................... Lighting ConductorJohn Logie Baird ..................Mechanical TelevisionRutherford .................................................. Proton-

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