summative grade 11 ap biology

7/31/2019 Summative Grade 11 AP Biology

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Summative Grade 11 AP Biology

Prokaryotes

Prokaryotes are extremely common

Can be found almost everywhere (bacteria)o Soil

o Air

o On organisms/in them

o Every possible place that has favourable living conditions

Archaea can also be found in extreme conditions

Their collective mass is at least 10 times that of all eukaryotes

Bacterial Cell Wall

Formed by peptidoglycan

Stain either Gram-positive or Gram-negative (see classifying bacteria)

Peptidoglycan encloses the entire bacterium and anchors other molecules that

extend from its surface.

Difference from plant cell wall: plant cell walls are formed mainly by cellulose

Classifying Bacteria

Gram stain, developed in the 19th century

Gram-positive bacteria have similar walls with a relatively large amount of

peptidoglycan (thick protein layer on their cell wall and stains purple)

Gram-negative bacteria have less peptidoglycan and are structurally more complex,

with an outer membrane that contains lippolysaccharides. (carbohydrates bonded to

lipids.) (thin protein layer on their cell walls and stain pink) Classified by shape, structure of their cell walls, and their source of food and

energy

Bacterial phylogenies have been constructed based on analysis of RNA sequences

Genetic change by mutation occurs rapidly in bacteria

Genetic differences can arise in bacteria populations within a few generations

Bacterial Locomotion

Flagella- may be scattered over the entire cell surface or concentrated at one or bothends of the cell

Taxis- movement toward or away from a stimulus, chemotaxis- respond tochemicals by changing their movement patter

Ex: movement toward nutrients/oxygen (positive chemotaxis), away from toxic

substances (negative chemotaxis)

Bacterial Reproduction (asexual)

Binary Fission


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Bacteria makes copy of its single chromosome, and when cell reaches a certain

size, it elongates and separates the two chromosomes (chromosomes attached tocell wall by cytoskeleton). The cell then builds parition between them and the

septum forms

Septum is completed and distinct cell walls form

Genetic Modifications of Bacteria

Conjugation

Two bacteria cells are linked to each other through pilus (bridging structures)

One bacterium transfers all or part of its chromosome to another across the pilus

Receiving cell undergoes binary fission to produce more cells with the new gene

contentTransformation

The modification of genotype of a cell by the introduction of DNA from another

source

Ex: plasmid (small loops of DNA separate from the main chromosome), contains

one to few genes, these genes are different from those found in the chromosomes,can split from the bacterial chromosome and rejoin it, important in producinggenetic recombination in bacteria

Transduction

Transfer of genetic material by phages (viruses) as they infect one cell to another

Nutritional Categories of Bacteria

Photoautotrophs

Use light as their source of the needed energy and CO2 to form organic compoundsPhotoheterotrophs

An organism that depends on light for most of its energy and principally on organic

compounds for its carbonChemoautotrophs

Use CO2 and oxidize inorganic substances to obtain energy

Chemoheterotrophs

Oxidation/consummation of organic molecules to generate energy and to obtain

carbon

Classification of Prokaryotes into two DomainsCarl Richard Woese defined Archaea in 1977 by phylogenic taxonomy of 16S ribosomal

RNA, a technique pioneered by Woese. Molecular systematics is the use of the structure of

molecules to gain information on an organisms evolutionary relationships. The study ofrRNA molecule led him to conclude that Archaeans are more closely related to Eukaryotes

than bacteria, thus forming their own group.

Ecological Significance of Prokaryotes

Bacteria: decompose detritus and turn organic carbon into inorganic carbon

Nitrogen fixing bacteria (nutrients for plants) and denitrifying bacteria

Symbiotic relationships with eukaryotes


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Key characteristics of the three domains

Domain Characteristics

Bacteria Cocci, bacilli, and spirals

Most unicellular, some species form colonies

Membrane-bound organelles absent Peptidolycan in cell walls

Circular chromosome

Nucleoid

RNA polymerase: 1

Rare introns

Antibiotics inhibit growth (streptomycin and chloramphenicol

Histones associated with DNA absent

Initiator amino acid for protein synthesis: Formyl-methionine

Membrane lipids- unbranched hydrocarbons

Archaea

Membrane-bound organelles absent Nuclear envelope absent

Peptidoglycan in cell wall absent

Membrane lipids : some branched hydrocarbons

Several kinds of RNA polymerase

Introns present in some genes

Antibiotics dont inhibit growth (streptomycin and

chloramphenicol

Histones associated with DNA present

Circular chromosomes

Initiator amino acid for protein synthesis: Methionine

Eukarya Nuclear envelope present

Membrane-bound organelles

Peptidoglycan in cell wall absent

Membrane lipids: unbranched hydrocarbons

RNA polymerase: several kinds

Initiator amino acid for protein synthesis: Methionine

Introns present

Response to the antibiotics streptomycin and chloramphenicol:

Growth not inhibited

Histones associated with DNA present

Eukaryotes

Protists Diversity

Most protests are unicellular, although there are some colonial and multicellular species.

At the cellular level, many protists are the most nutritionally diverse of all eukaryotes.

There are autotrophs, heterotrohps, and mixotrophs. There habitats are also very diverse.


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Most protists are aquatic, and are found almost anywhere with water. They are important

constituents of planktons. Reproduction and life cycles are highly varied. All three basic

types of sexual life cycles are represented among protists, along with some variations thatdo not quite fit any of types. Asexual reproduction. Too many structural and functional

differences among them.

Genesis of eukaryotes from prokaryotes

Endosymbiosis- origins of mitochondria and plastids(chloroplasts)

- according to this theory, these organelles originated as separateprokaryotic organisms that were taken inside the cell as endosymbionts.

Kindom Characteristics

Protista Heterotrophs and autotrophs

Most are single celled

Eukaryotes

Do not fit in other kingdoms

Less diverse than bacteria, more diverse than other eukaryotickingdoms

Fungi Heterotrophs- feed by releasing digesting enzymes into theirsurroundings, absorb the digested nutrients into their cells

Few are unicellular

Boundary of a fungal cell is a cell wall made of chitin insteadof cellulose

Hyphae+septa

Sexual+asexual reproduction

Plants Vascular + non-vascular

Autotrophs Roots, stems, leaves

Alternations of generations

Cellulose cell walls

Have chlorophylls a and b

Photosynthesis

Aquatic or terrestrial

Gymnosperms or angiosperms

Multicellular

Eukaryotes

Mostly sexual reproducation

Animalia Multicellular

Eukaryotes

Reproduce sexually

Ingest food

Aerobic

Heterotrohps

Herbivore, omnivore, carnivore


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Kingdom Fungi

Acquiring Nutrients

Hyphae grows across a source of food (dead matter)

Release digestive enzymes

Enzymes break down large organic molecules in the substrate into smallermolecules

Smaller molecules diffuse into the fungus for growth and repair (extracellulardigestion)

More extensive the mycelium, greater surface area available for absorbing nutrients

Some are parasites of plant and animals that specialized to feed on living cells, their

hyphae is called haustoria that penetrate host cellsHyphae is a network of fine filaments. Mycelium is a loose, branching network of hyphae

(Hyphae strung together form a network called mycelium)

Fungal Cell Walls

Chitin, a protein that makes up the cell wall of fungus cells

Contributions to an EcosystemDecomposers: break down organic waste and release nutrients into the soil

Performing essential recycling of elements between the living and nonliving

worldThey form symbiotic relationships with plants, algae, and animals.

We eat fungi.

Use others to make cheeses, alcoholic beverages and bread

Antibiotics produced by fungi treat bacterial infections

Fungi is leading to applications in biotechnology

Phyla of Fungi

Phylum Characteristics

Zygomycetes Saprotrophs, few parasites of protests and small invertebrate

animals, mostly terrestrial, ex: Rhizopus stolonifer (black breadmold), Pilobolus (grows on animal dung)

Basidiomycota Have short lived reproductive structure ex: mushrooms, rusts,smuts, shelf fungi/bracket fungi

Ascomycota Largest group of fungi, have asci, mostly saprotrophs, parasites

of plants, sexual reproduction ex: truffle, Aspergillus nidulans

Chytridiomycota Water mould -Allomyces sap, Batrachochytrium dendrobatiolisBlastocladiomycota

Neocallimastigomycota

Glomeromycota


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Kingdom Animalia

Hypothesis for the origins of Animals

Most systematics now agree that all animals lineages are monophyletic; that is, we can

trace all lineages back to a single common ancestor. The ancestor was probably a

flagellated protist; which was probably related to choanoflagellates.

Two forms of symmetry of the Eumetazoa (clade comprising all majoranimal groups

except sponges, placozoa and several other little known animals)Bilateral : has a left and a right side, one line of division that allow the body to be divided

into equal but opposite parts

Radial: parts of animal radiate from the centre. Any imaginary slice through the centralaxis divides the animal into mirror images

Cephalization as an Evolutionary TrendThe nervous tissue, over many generations, becomes concentrated toward one end of an

organism. This process eventually produces a head region with sensory organs. The endof a traveling animal that is usually first to encounter food, danger, and other stimuli.

development of central nervous system and adaptation for movement on land.

Germ Layers of Radiata and other Eumetazoa

Radiata contain two germ layers including the ectoderm and endoderm, the otherEumetazoa differ in that they have an additional layer called the mesoderm.

Classifying Animals

Term Significance

Acoelomates Animals with no blood vascular system and lacking a cavity

between the gut and outer body wall ex: flatworm-major split in phylogenic tree for animal development involved the

split of bilateral organisms into two further branches

Pseudocoelomates Animals with fluid-filled body cavity that is not enclosed by

mesoderm (body cavity formed from the blastocoel) ex:roundworms

Coelomates A coelom is a fluid-filled body cavity found between the body walland gut that has a lining. It comes from the mesoderm.

Protostomes Branches from Coelomates, a bilateral animal whose first

embryonic indentation eventually developes into a mouth (mouthdevelops from blastospore) ex: annelids, arthropoda, mollusks

Deuterostomes A branch from Coelomates that includes chordates andechinoderms. The first indentation of their embryos eventually

develops into the anus (anus develops from blastospore)

Blastospore: the indentation that during gastrulation leads to the formation of the

archenteron
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Major differences between Protostomes and Deuterostomes

Protostomes: blastospore develops into mouth and the second opening forms the anus

Early cell division: cells specialize, determined cleavageCoelom formation: schizocoelous-coelom originates as a split within a bud of

mesodermal tissue at time of gastrulation

Deuterostomes: blastospore develops into the anus and the second opening forms themouth

Early cell division: undetermined cleavage

Coelom formation-enterocoelous: coelom originates from an out pocketingof the archenterons during gastrulation

Phyla of Animalia

Phylum Characteristics

Ponifera Sponges

Cnidaria Polyp/medusa, ex: jellyfish

Platyhelminthes Flatworms

Annelida Segmented worms, long tube like bodies, each segment containsimilar sets of organs for excretion, circulation, nerve control

Mollusca Soft-bodied animals

Arthropoda Joint legged animals, body segments, hard external cuticle, legs

divided into moveable segments, ex: spider

Echinodermata Starfish

Chordata Vertebrate/invertebrate

Sponges and their method of NutritionSponges filter their food from passing stream of water.

The body has a single opening food enters, waste matter leaves

A sponge is long and cylindrical with an opening in the middle.They have no tissue or organs.

Unique characteristics of Cnidarians

These organisms are of radical symmetry

Lack a mesoderm

Body is a digestive sac that can be one of two types

Use tentacles to capture and eat prey

Body plan is a sac like with a central digestive compartment, with

gastrovascular cavity and it has a single opening

The two shapesPolyp (asexual): cylinder-shaped and lives attached to some surface

Medusa: flat and roams the waters looking for food


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Platyhelminthes

Evolutionary Significances

Structurally more complex

3rd embryonic layer, mesoderm, contributes to the development of more

complex organs and organ systems, including true muscle tissues

Significance to Humans cause troublesome diseases in humans

tapeworms reside in the enteron or the biliary ducts of mammals

parasites on humans

cause much suffering and sometimes death

cause diseases in livestock which can cause problems for humans

some parasite on neural system

Parthenogenesis

Biological reproduction that involves development of a female (rarely male) gametewithout fertilization. It occurs commonly among lower plants and invertebrate animals,

particularly rotifers, aphids, ants, wasps, and bees. An egg produced parthenogeneticallymay be either haploid or diploid.

Unique Structure and Function of the Pseudocoelomates

Mesoderm discontinues with regard to endoderm but not contact withectoderm

Provides anchor matrix of muscle fibres etc. derived from suspension of

digestive system; fluid-filled cavity, therefore hydrostatic pressure provides

support for overall body structure and shape of organism.

Nematodes and Humans

Are roundworms found in moist environments

Trichinosis is caused by a roundworm that infects meat products (usually

pork)

Humans ingesting infected meat can become afflicted with this disease

Parasites of humans

Important role in decomposition and recycling nutrients

Research specimens (aging in humans)

Agricultural pests that attack roots of plants

Body Regions of a Mollusk

Muscular footVisceral Mass

Mantle

Mollusks and Annelids

The life cycle of many marine molluscs includes a ciliated larvae called the trochophore,

also characteristics of marine annelids and other Protostomes. But mollusks lackthe one trait that most defines annelid heritage: true segmentation.


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AnnelidsEvolutionary significance

Muscles work against the non-compressible coelic fluid, a hydrostatic skeleton

Muscles can alter the shape of each segment individually because the coelom isdivided into separate compartments.

Segmentation

Segmentation allows for a high degree of specialization of body regions. Thisregional specialization is an evolutionary development of the body plan of

arthropods. Easier motility

Parapodia (pair of them) (satae) that function in locomotion (in each segment of a

polychaete)

Arthropoda

Success

Greater diversity in distribution and numbers than any other phyla ofAnimalia

Have adapted successfully to life in water, on land, and in air

Live on top of mountains, at great depths in the ocean and in Antarctica

Can survive extremes of temperature, toxicity, acidity and salinity

Characteristics for the Success

Hard external cuticle, acts as an exoskeleton for muscle attachment

Segmentation

Jointed legs

Coelomate Deuterostomes: echinoderm and chordata, mammals

Unique Traits of Echinoderms

Water vascular system- a network of hydraulic canals branching into

extensions called tube feet (podia) that function in locomotion, feeding and

gas exchange

By expanding or contracting various chambers in the water vascular system,

water is forced into the tube feet, extending or retracting them and allowingechinoderms to walk

Majority benthic organisms (live on sea floor)

Most show pentamerous radial symmetry

Bilaterally symmetrical larvae

Characteristics of Chordates

Have a dorsal nerve cord, and from it, nerve braches to all parts of the body

Have a notochord which is a rod of cartilage that runs along dorsal length of

body

In most vertebrates, notochord only occurs in embryo


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Have gill slits in pharynx (throat), terrestrial vertebrates only have them in

embryonic stage.

Example of an invertebrate chordate: a tunicate, hagfishes- they lack a series of backbones

in their body

-UrochordataPaedogenesis

Reproduction by an animal that is still in the larval or pre-adult form. Paedogenesis is a

form of neoteny and is particularly marked in the axolotl, a larvae form of salamander,which retains its larvae features owing to a thyroid deficiency but can breed, producing

individuals like itself. If the thyroid hormone thyroxine is given, metamorphosis occurs.

An example is the mudguppy, which retains gills and other larval features when sexuallymature.

Characteristics of Subphylum Vertebrata

Series of bones that make up the back bone

Craniates (having more complex nervous system)

Significance of being a Tetrapod

4 feet

limbs that can support their weight on land and feet with digits that allow

them to transmit muscle generated forces to the ground when they walk

live on land

bones of the pelvic girdle, to which the hind legs are attached, are fused to

the backbone, permitting forces generated by the hind legs against theground to be transferred to the rest of the body.

Amniotic Egg and the AmnioteAmniotic egg contains specialized membranes that protect the embryo (humans --> amniotic

sac). The shell around the egg slows dehydration. Amniotes also have skin thats less

permeable and the ability to use the cage to ventilate the lungs. This allowed tetrapods toreproduce on land.

Major Branches of Subphylum Vertebrata

Class Characteristics

Aves Endothermic, feathered over much of body surface; scales on legs andfeet; bones hollow and light-weight in flying species; four chambered

hear; well developed lungs and air sacs for efficient gas exchange

Reptilia Have scales that create a water proof barrier, lay shelled eggs on land,ectothermic; most have three chambered hearts; internal fertilization;

amniotic egg typically laid on land

Mammalia Mammary glands which produce milk; hair; generally larger brain than

other vertebrates of equal size; endothermic; subcutaneous fat; hair; most

viviparous; suckle young with milk produced from mammary glands; fourchambered heart; most have four legs;

Amphibia Most have moist skin that complements the lungs in gas exchange


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Osteichthyes Bony fishes; bony endoskeleton; aquatic; ectothermic; well developed

respiratory system, usually involving gills; possesses swim bladder;paired fins; divided into two groups: ray finned fishes (which include

most living species) and lobe finned fishes (which include the lungfish

and coeloacanth)

Agnatha Jawless fishes-exclude all jaw fish (vertebrates)Cephalochordata Lancelets- larvae filter feeders; adults parasites whose circular mouth is

lined with rasping toothlike structures; many live in both salt water and

fresh water during the course of their lives

Chondrichthyes Cartilaginous fish: have jaws; most live in salt water; typically several gill

slits; tough small scales with spines; ectothermic; two chambered heart;

male possesses structures for internal fertilization

Kingdom Plantae

Characteristics of all Plants apical meristems

alternation of generations

walled spores produced sporangia

multicellular gametangia

multicellular dependent embryos

Advantage of Living on Land

more sunlight

more access to CO2

more habitat more nutrients

Tissue in Land Plants (most of them)

The vascular tissue (includes the xylem and phloem transport materials to all parts of the

plant

xylem: water superhighway for the plant, transporting water throughout theplant

the phloem: transports sugar and nutrients to the various plant structures

Major groups of Plants

Non-vascular plants- without vascular tissue (bryophytes: mosses)Vascular plants- with vascular tissue (angiosperms and gymnosperms)

Reproductive Strategies

Non-vascular plants require moist habitats because their sperms must swim throughwater to fertilize the ovule.

Vascular plants can live in dry climate because they do not require water for fertilization.

They can use wind and animals.


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Ferns

Water dependenceFern species live in a variety of habitats, from remote mountain elevations, to dry

desert rocks faces, to bodies of water or in open fields. Some live in extremely

acidic habitat and other live in basic ones. They are vascular plants and do notrequire a lot of water even though they lack seeds and flowers. Although their

preferred habitat is a moist one, they can survive in dry areas as well. They do not

entirely depend on water for reproduction.

Major Groups that Reproduce Using Seeds

Gymnosperms- naked seeds

Angiosperms- flowers plants

Significance of the Angiosperms

Protect their seeds within the body of a fruit

Seeds are better protected of nutrients

Can be carried to farther places and can be displaced farther than those of

gymnosperms

Flowering plants

Major Strategies for Plant pollination

Seeds (gymnosperms + angiosperms)

Anemophily (wind)

Hydrophily (water)

Biotic pollination : organisms that transport pollen

Entomophily (insects)

Zoophily (vertebrates, ex: birds and bats)

Development of Fruit

Various fruit adaptations help disperse seeds

Dandelions: fruit function like propellers--> wind

Coconuts: dispersal by water

Burrs: cling to animal for dispersal

Edible fruits: animal eats --> deposit seeds with feces--> acts like fertilizer

It helped plants to be dispersed to a larger area and become more wide spread. Their seeds

are also protected.

Virus

Living Things?

Not considered living things

Have no cellular structure


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No cytoplasm, organelles or cell membranes

Do not carry out respiration or any other common life processes

Consist of little more than strands of RNA or DNA surrounded by a

protective protein coat called a capsid

Parasite cells; capsid protects the virus from attacks by the host cell

enzymes.

Structure of Virus

Tobacco mosaic virus : helical capsid with the overall shape of a rigid rod

Adenoviruses: a polyhedral capsid with a glycoprotein spike at each vertex

Influenza viruses: outer envelope studded with glycoprotein spikes. Thegenome consists of eight different RNA molecules, each wrapped in a

helical capsid

Bacteriophage T4: like T-Even phages, has a complex capsid consistingof a polyhedral head and a tail apparatus

Depending on the virus, the capsid may be rod-shaped, polyhedral, or more complex shape

Characteristics that led to a Classification of Viruses into 21 Groups

Life Cycle

Lytic cycle1. Attachment

2. Entry: the virus inject its nucleic acid into the host cell

3. Replication: hosts metabolism replicates the viral RNA or DNA

4. Assembly: new virus particles are assembled5. Lysis and Released: host cell breaks open and release new viruses

Life Cycle of Provirus

Enzyme called reverse transcriptase causes the host cell to copy the

viral RNA into DNA

Viral genome can enter the chromosomes of the host cell and can be

copied whent the cell divides

Virus is now called a provirus

When host cell undergoes mitosis, it replicates the provirus

Process can continue for years and does not kill host cell

However, provirus can separate from host chromosomes and

complete the lytic cycle

Why Viruses are Important for Humans


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Biotechnology

The gene is spliced into the genome of a virus

The virus gets copied with the gene through host cell

Helps genetic engineers

Cancer Research

Can possibly cure cancer Still under research

People who had cancer and caught a severe virus and survived are cancer

free

Origin of Viruses

Scientist believe that they evolved after the first cells

They cannot replicate without host cells

Probably originated as fragments of nucleic acid that escaped their original

acid

Survived by becoming parasites of same or similar types of cells

Taxanomy

Taxa

Domain

Kingdom

Phylum

Class

Order Family

Genus

Species

Binomial Nomenclature

Two-word name for each species

Latinised and first word always describe the genus of the species

First letter of the first word is always capitalized

Second word is a particular name given to the species that no other species

have within the same genus

Common names are misleading; same name can be given to two completely

different species

With scientific naming, no two species have the same name

Sources of Genetic Variety

Mutation

Meiosis (sexual reproduction)


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Meiosis allows different gene combinations

Crossover occurs where homologous chromosomes have the potential toexchange bits of DNA

Two haploid cells fuse, create a cell with a brand new set of DNA that has

never been formed before

Carry adaptations to survive their environment

Determining Relatedness

Fossils: ancestral characteristics that may have been lost over timeBiochemical evidence: similar protein structures; compare different proteins of organisms;

more similar, more closely related

DNA evidence: compare introns; the bigger the difference, the longer ago the two animalsbranched from each other

Homologous organs: similar developmental origins, different adult functions

Vestigial Organs: structures or organs that seem to serve no useful function

Cladistics and Cladograms Cladistics is a classification scheme based on phylogeny

System based on the idea that each group of related species has one

common ancestor

Organisms retain some ancestral characteristics as they evolve and diverge

from one common ancestor

Cladogram is a branching diagram that resembles a phylogenic tree, but can

be used to test alternative hypotheses

One common ancestor, branches are drawn to represent differentevolutionary processes that took place and the organisms that evolution

created

More recent the group split, more related they are

Monophyletic, paraphyletic, polyphyletic (Look on Wikipedia for more

information)

summative grade 11 ap biology

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