biology knowlegde
TRANSCRIPT
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
© Copyright Template Berri DwiPutra 2012
UNIT 3Movement in and out of cells
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
3.1DIFFUSION
Diffusion is net movement of molecules from high concentration gradient to lower concentration gradient
Concentration gradient is the difference between the concentration of molecules in two places
Factors that affect diffusion :• Distance• Concentration gradient• Surface area• Temperature• Size of molecules
A Solution is made up of two parts, the solute and the solvent
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
3.2OSMOSIS
Osmosis is diffusion of water from a dilute solution into a more concentrated solution through a partially permeable membrane.
A Partially permeable membrane allows small molecules such as water to pass through but not large solute molecules.
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
3.3Osmosis in plant and animal cells
TurgidityTurgidity is the process where the condition of water potential insurrounding of cell is bigger than inside of cell so water move into the celland the cell become turgid or hypotonic
Plasmolysis is the process where the condition of water potential inside ofthe cell is bigger than in surrounding of cell so water move out of the celland the cell become flaccid or hypertonic
Plasmolysis
Osmosis in animal cells : Hysotonic
Isotonic
Hypertonic
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
3.4Active transport
Active transport is the movement of ions or molecules across thecell membrane, against a concentration gradient, using energyfrom respiration
Active transport need energy to change the shape of carrier protein as the way of ions to move in or out of cell
BIOLOGY SHOWLIVE
BIOLOGY SHOWLIVE
BIOLOGY SHOWLIVE
BIOLOGY SHOWLIVE
BIOLOGY SHOWLIVE
BIOLOGY SHOWLIVE
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
UNIT 4
ENZYMES
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
4.1Structure and action of enzymes
Enzyme is a biological catalyst that speed up a chemical reaction and all enzymes are proteins
How enzymes work :1. Anabolisme, Breaking large molecules into small ones2. Katabolism, Building up large molecules from small ones3. Converting one small molecules into another
Two Theory about Enzymes Lock and key theory Induced fit
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
4.2Factors affecting enzyme action
Effect of temperature on enzymes
Increasing the temperature of an enzymes- controlled reaction increase the rate of reaction up to a maximum, which occurs at the optimum temperature. At higher temperatures the rate of reaction decreases quickly until it stop acting and denaturate.
Enzymes and pH
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
4.3Enzymes in industries
Biological washing powders : Proteases – break down protein stains, e.g. blood, grass and egg. Lipases – break down fats in grease stains, e.g. butter, lipstick mayonnaise.Amylases – break down starch, e.g. food stains containing starch.Cellulases – break down cellulose fibres.
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
UNIT 5
NUTRITION
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
5.1Nutrients
Nutrition is the obtaining of food to provide energy and substances needed for growth and repair.
Seven different nutrients needed for a balanced diet for human are :1. Carbohydrate2. Protein3. Fats4. Vitamins5. Minerals6. Fibre7. Water
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
5.2Chemical test for nutrients
Testing for starch – iodine solutionTesting for sugars – Benedict’s solutionTesting for protein – biuret solutionTesting for fats – ethanol
5.3Sources of nutrients
Carbohydrates : rice, potatoes, bread, yams, sugar and honey.Protein : meat, fish, milk and nuts.Fats : butter, cheese, fat in meats and fish, nuts.Water : H2OVitamins and minerals : oranges, lemons, milk, butter, liver, egg, green vegetables, etc.Fibre : cabbage, sweetcorn, and celery
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
UNIT 6
Plant nutrition
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
6.1Photosynthesis
Photosynthesis is the process by which plants make glucose from raw materials using energy from light.
Carbon dioxide and water are the raw materials for photosynthesis.
Chlorophyll absorbs light energy that is used in photosynthesis.
6CO2 + 6H2O light and chlorophyll C6H12O6 + 602
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
6.2What is needed for photosynthesis?
The requirement for photosynthesis:• Light, which provides energy for the process• Chlorophyll, a green pigment that absorb the energy from light .•Carbon dioxide, which diffuses into the leaves from the air.• Water, which is absorbed by the plant’s root from the soil.
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
6.3Product of photosynthesis
• glucose is used for respiration.• some glucose is changed into starch• some glucose is used to make cellulose• glucose is converted to sucrose• glucose and nitrate are used to form amino acid• sugars are convert to oils
Oxygen is a by-product of photosynthesis
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
6.4Rate of photosynthesis
A limiting factor is something in such short supply that itrestrict life processes.
Limiting factors of photosynthesis are : •light intensity •Temperature•carbon dioxide concentration.
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
6.5Glasshouse production
Condition inside a glasshouse allow plants to :• grow earlier in the year• grow in places where they would not normally grow well
The following condition inside glasshouses are controlled. Temperature Light Carbon dioxideWater
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
6.6Leaves
Leaves have : a large surface area – to absorb light rays a thin shape – so gases can diffuse in and out easilymany chloroplasts – to absorb light for reaction that take places in photosynthesis veins – to support the leaf surface and to carry water and ions to the leaf cells, and to take sucrose and amino acid away from the leaf to all other parts of tbe plants.
Stomata usually open during the day and close at night
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
6.7Mineral requirements
Plant nutrients I. Nitrate ions to make amino acid which are used to
make proteins.II. Magnesium ions are absorbed by plant and used
to make chlorophyll.III. Phosphate for making compounds such as DNA
and for respiration.
FertilisersI. Nitrogen for growth of leaves and
stems.II. Phosphorus for healthy roots.III. Potassium for healthy leaves and
flowers.
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
UNIT 7
Animal Nutrition
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
7.1A balanced diet
A balanced diet provides an adequate intake of the nutrients and energy needed to sustain the body and ensure good health and growth.
A nutrients is a substance in food that provides benefit to the body.
Three basics function of nutrients :o To provide Diet depends on age, sex and activity energyo To allow growth and repairo To regulate the body’s metabolism
Diet depends on age, sex and activity
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
7.2Balancing energy needs
Energy intake is the energy from the food in a day in carbohydrates, proteins and fats.
Energy output is the energy that is used by body in a day.
OBESITYCAUSED BY :• high intake of fatty food• too little exercise• social and emotional stress
How could someone lose weight?They could :• Eat less high-energy foods• Take more exercise
A sensible approach to slimming should combine :• a balanced diet with a lower intake of energy• a gradual increase in exercise• having an ideal, but achievable
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
7.3Digestion
Digestion is the breakdown of large , insoluble food molecules into small, water-soluble food molecules so that can be absorbed into the bloodstream.
Mechanical digestion isthe breakdown of largepieces of food into smallerpiece of food withoutchanging the foodmolecules.
Chemical digestion is the breakdown of the large food molecules into smaller molecules by the action of enzymes.
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
7.4Teeth
• incisors are chisel-shaped for biting and cutting.• canines are pointed for piercing and tearing.• premolars have aneven ‘cusps’ for grinding and chewing.• molars are like premolars and for chewing up the food.
Adult humans have 32 teeth : 8 incisors, 4 canines, 8 premolars, and 12 premolars.
Tooth decay is caused by bacteria in plaque, which changes sugar to acid that attacks the enamel and dentine of the tooth.
Tooth decay can be avoided by regular brushing with a good toothbrush, avoiding sugary food and visiting the dentist regularly.
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
7.5The stomach and small intestine
Peristalsis involves a wave of muscular contraction that squeeze the food bolus, carrying it down the oesophagus to the stomach.
The stomach is a muscular bag that usually holds about 1 liter of food but can stretch to accommodate more.In the stomach, food is churned up and mixed with gastric juice and hydrochloric acid. This start the digestion of protein.
In the small intestine, there is pancreatic juice that contain :• amylase – breaks down starch to maltose.• trypsin – a protease that breaks down protein and polypeptides to peptides.• lipase – breaks down fats to fatty acid and gliycerol.
BIOLOGY SHOWLIVE
© Copyright Template Berri DwiPutra 2012
7.6Absorption and assimilation
Absorption is the movement of digested food molecules through the wall of the intestine into the blood or the lymph.
Assimilation means that the food molecules that have been absorbed now become part of the cells or are used by the cells.• Stores glucose by removing it from the blood and storing it as glycogen.• Uses amino acid to make protein.• breaks down excess amino acid.• converts fatty acid and glycerol into fats.• produces cholesterols from fats.
BIOLOGY SHOWLIVE