biology exam

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Define gene.

DNA code for a characteristic or traits

Different versions of the same gene are called:

alleles

What is a fossil?

physical evidence of an ancient organism

What are types of fossils?

mold/cast: imprint which gets filled in

carbonization: carbon left behind

permineralization: minerals replace organic compounds

unaltered: organism still intact (tar, frozen, amber)

trace: tracks, nests, coprolites

Define natural selection.

individuals with adaptive traits tend to have higher survival rates, and higher fitness resulting in a higher frequency of those alleles through the generations

Define population.

all off the individuals of a particular species in a given area

Define allele frequency.

The number of times an allele occurs within the gene pool

Define gene pool.

all of the alleles of all the genes in a population

Who wrote "On the Origin of Species"?

Charles Darwin

What are the patterns of Natural Selection?

directional, stabilizing, disruptive, sexual

Describe directional selection

a form of a trait on one end of a scale is adaptive (black or white pepper moths with smog)

Describe stabilizing selection

an intermediate form is adaptive (baby birth weight)

Describe disruptive selection

extreme forms are adaptive (seed cracker beak size)

Describe sexual selection

organisms are better at scoring mates so have higher fitness (birds)

What is another name for Natural Selection?

survival of the fittest

What are the types of Nonselective Evolution?

founder effect, inbreeding, and gene flow

Describe the founder effect.

a small group starts a new population

Describe inbreeding.

mating between close relatives

Describe gene flow.

movement of alleles between populations

What is isolation?

When populations are cut off from eachother

Describe temporal isolation

due to timing (cicadas)

Describe behavioral isolation

courtship displays lead to preferences which give specific organisms higher fitness (birds)

Define speciation

species can no longer interbreed due to isolation, so a new distinct species is made

Describe allopatric speciation

a physical barrier divides populations

Describe sympatric speciation

no physical barrier (typically due to to prefernce)

What is a coevolution?

interaction between two species cause them to evolve together

Explain how plants and pollinators have coevolved.

plants have one specific pollinator insect

What is phylogeny?

Evolutionary history of a species

What evidence leads us to believe that plants evolved from green algae?

plants share many characteristics with algae: cellulose, cell walls, chloroplasts with chlorophyll

What is alteration of generations?

life cycle in which organisms have both haploid and diploid stages

Define the following structural adaptations of plants its importance: cuticle

waxy coverings over a plants surface

Define the following structural adaptations of plants its importance: stomata

pores in cuticle that open for gas exchange and close for water conservation

Define the following structural adaptations of plants its importance: Vascular tissues

internal pipelines which transfer water and nutrients throughout plant

Define the following structural adaptations of plants and its importance: xylem and phloem

xylem: carries water and ions up from root

phloem: carries sugars from photosynthesis

Describe the bryophytes.

simplest plants, no seeds, non-vascular, no phloem/xylem

What are the three main examples of bryophytes?

liverworts, hornworts, and mosses

Which is the most common bryophyte?

mosses

What is sphagnum?

peat moss which grow in peat bogs

What can sphagnum be used for?

potting soils, fire fuel

Explain why seedless vascular plants still need to live near water.

their sperm still have to swim with flagella

What are fiddleheads?

young fronds of ferns (baby ferns)

Describe what gymnosperms are.

naked seeds (no fruit)

What are some examples of gymnosperms?

cycads, conifers, gnetophytes (pines, spruce, fur)

What are the types of cones in conifers?

pollen/ stamen cones (males) and ovule/egg cones (female)

What will develop into a fruit in the Angiosperms?

the ovary

Define angiosperms.

flowering plants

What two structures allowed angiosperms to succeed?

flowers and fruits

What are some medications we get from plants?

aspirin, caffeine, nicotine, marijuana, opium

Contrast monocots and eudicots.

mono: scattered bundles within stem, one cotyledon, parallel veins, three part flower parts, fibrous roots

eudi: bundles in rings within stem, two cotyledons, branched veins, four/five flower parts, tap roots

Distinguish between shoots and roots.

shoots are above ground growth, roots are below ground

Describe woody stems.

hard and brown

Describe herbaceous stems.

soft and green

Where does wood come from?

secondary xylem

How are growth rings formed in wood?

each year, the growth of the secondary xylem forms a new ring

Describe and give examples of these stem specializations: bulbs

short stem surrounded by overlapping, modified leaves (onions, tulips, daylilies)

Describe and give examples of the stem specializations: tubers

storage structures from stolons or rhizomes (potatoes, carrots)

What are the main photosynthetic organs of plants?

leaves

List and describe two basic forms of roots.

fibrous: netlike, more surface area

tap root: long major root with branches

What are the functions of roots?

takes up water and ions, anchors plants

What are the functions of root hairs?

to increase surface area

What is transpiration?

the evaporation of water from plants

Contrast perfect and imperfect flowers.

perfect have both stamens and carpels (male and female parts) so they can self pollinate

imperfect have stamen OR carpels and can only cross pollinate

The long strands of filaments that make up the body of a fungus is called \_____?

hyphae

What are the ways fungi are not similar to plants?

not photosynthetic, cell walls of chitin, no cellulose, heterotrophic decomposers

What roles do fungi play in the ecosystem?

decomposers, recyclers, and colonizers

What type of fungus is killing off amphibians all over the world?

chytrid

Describe the following mutualistic relationship in fungi: Mycorrhizae

increases surface area of roots

Describe the following mutualistic relationship in fungi: Lichens

grows where plants can't w/ photosynthetic algae/bacteria

Describe the parasitic fungus that causes zombie ants.

takes control over the brain and forces the ant to climb so it can release spores

List and describe fungal infections in humans.

athletes foot, ringworm, yeast infections, thrush; result in odor, discomfort, irritation, rashes, and illness

Describe ways humans can use fungi for food.

mushrooms, morsels, and truffles

Describe ways humans can use fungi for fermentation.

bread rising, alcoholic beverages, and ethanol fuel

Describe ways humans can use fungi for medicines.

penicillin, antibiotics, ergotamine (migraines), psilocybin (depression)

List the characteristics of animals.

Heterotrophic, multicellular, eukaryotic, cells lack cell walls, sexual reproduction, motile

List animal body plans.

asymmetry, bilateral symmetry, radial symmetry

Describe asymmetry.

no symmetry

Describe bilateral symmetry.

left and right sides mirror eachother

Describe radial symmetry.

symmetry around a central axis

Define cephalization.

nerve cells/ sensory structures on head (brain)

List the different types of digestie (gut complexities)

intracellular, gastrovascular cavity, complete digestive tract

Describe intracellular gut complexity.

simple, individual cells digest food

Describe gastrovascular cavity gut complexity.

one opening for both food and waste

Describe complete digestive tract gut complexity.

complex different sections for digestion

Define coelom and coelomate.

body cavity around digestive tract; organism with a coelom

What animals do not have tissues or organs?

sponges

What is the osculum?

large opening at the top of the sponge

What animals has an osculum?

sponge

What are the body forms of a cnidarian.

polyp and medusa

Describe the polyp body form

A cylindrical body, with a mouth atop the cylinder, surrounded by tentacles.

Describe the medusa body form

An umbrella shaped body, with the mouth pointing down and surrounded by hanging tentacles. Free floating

What are the two tissue layers in the cnidarians body?

epidermis and gastrodermis

What separates the two tissue layers in the cnidarians body?

mesoglea

What are cnidocytes?

stinging cells

Describe the planarian.

common flatworm w/ bilateral symmetry, eyespots, and a ganglion

How many pairs of hearts do earthworms have?

5

What specific organisms have a radula?

chitons, snails, and slugs

What is a radula?

tongue hardened with chitin

List and describe characteristics of gastropods.

large muscular foot, head w/ eyes, radyla, calcified coiled shell (snails and slugs)

What structure secretes the shell in bivalves?

mantle

Describe cephalopods

"head-foot" foot modified into arms/ tentacles; smartest, fastest, and biggst invertebrates (squids, nautiluses, octopi, cuttlefish)