unit 7 part 1 (7.1-7.5)

Question 1

evolution

Answer 1

change in the genetic makeup of a population over time

Question 2

natural selection

Answer 2

process that organisms, having adaptions suited for a particular environment, have a greater chance of survival and reproduction, passing the adaptations to subsequent generations

Question 3

competition

Answer 3

organisms struggle with other organisms to get limited resources like space, food, mates, nutrients, light

Question 4

variation

Answer 4

genetic differences among organisms (mutations and sexual reproduction increase variation)

Question 5

adaptations

Answer 5

traits that provide an advantage in a particular environment, increase chances of survival and reproduction

Question 6

fitness

Answer 6

ability of an organism to survive and produce offspring

Question 7

reproductive success

Answer 7

production of offspring

Question 8

heritability

Answer 8

ability to pass on adaptations to successive generations

Question 9

what contributes to fitness?

Answer 9

heritability and reproductive success

Question 10

biotic vs abiotic

Answer 10

biotic is living things and abiotic is nonliving components

Question 11

populations are less likely to evolve in a __ environment

Answer 11

stable

Question 12

use and disuse

Answer 12

parts of the body that are used frequently become larger and stronger while others deteriorate

Question 13

descent with modification

Answer 13

unity of life is attributed to decent of all organisms from one ancestor that had modifications along the way

Question 14

artificial selection

Answer 14

humans modify other species by selectively breeding individuals for desired traits (dog breeding)

Question 15

key thing rizz wanted us to know

Answer 15

individuals do not evolve, populations evolve over time

Question 16

homology

Answer 16

similar characteristics that function differently

Question 17

vestigal structures

Answer 17

remains of features that served a function in the organism’s ancestors.

Question 18

convergent evolution

Answer 18

similar environmental conditions can select for similar traits in different populations or different species over time

Question 19

genetic variation

Answer 19

describes genotypic and phenotypic differences between individuals in a population

Question 20

selective pressure

Answer 20

any biotic or abiotic factors influencing survivability

Question 21

analougous structure

Answer 21

similar traits observedin distantly related or unrelated species

Question 22

darwins two observations

Answer 22

1) variations (same pop, diff traits)
2) more offspring than environment can support (everyone is fighting for survival because stuff is limited)

Question 23

darwins two inferences

Answer 23

1) survived have offspring, differential reproductive success
2) individual organisms do not evolve, adaptations are passe down

Question 24

order of natural selection

Answer 24

mutations -> variations -> selective pressure -> change in population

Question 25

mutations

Answer 25

contributes to changes in genetic makeup, creates genetic variation, provides new phenotypes to contribute to evolution

Question 26

genetic drift

Answer 26

chance events that cause allele frequencies to fluctuate unpredictibally from one generation to the next (especially in small populations)

Question 27

founder effect

Answer 27

few individuals become isolated from a larger population, the smaller group may establish a new population with a gene pool that differs from the source (ex: blown away by storm)

Question 28

bottleneck effect

Answer 28

sudden change in environment (fire, flood, etc) that dramatically reduces size of a population (by chance certain allels can over represent themselves)

Question 29

gene flow

Answer 29

transfer of alleles into or out of a population due to movement of fertile individuals or their gametes (ex: insects carrying pollen)

Question 30

relative fitness

Answer 30

contribution an individual makes to the gene pool of the next generation RELATIVE to the contributions of other individuals

Question 31

directional selection

Answer 31

occurs when conditions favor individuals at one extreme of the phenotypic range (shifts in pop frq curve in one direction, common when environment changes or migtation)

Question 32

disruptive selection

Answer 32

occurs when conditions favor individuals at both extremes of phenotypic range over intermediate phenotypes

Question 33

stabilizing selection

Answer 33

acts against both extremes an favors intermediate varients, reduces variation and maintains status quo of particular phenotypic character

Question 34

rapid repro =

Answer 34

increased mistakes!

Question 35

population

Answer 35

group of individuals of the same species that live in the same area and produce offspring (breed with eachother)

Question 36

gene pool

Answer 36

all copies of every type of allele in all members of the population, the deck of genes that is being continiously reshuffled

Question 37

hardy weinberg principal

Answer 37

helps us conclude whether population is evolving

Question 38

hardy weinberg equalibrium

Answer 38

frq of alleles and genotypes in a population will remain constant from gen to gen, if ONLY mendelian segregation and recominant alleles are at work

Question 39

5 conditions necessary for hardy equilibrium

Answer 39

1) large population (no genetic drift) 2) absence of migration (no gene flow) 3) no net mutation 4) random mating (no sexual selection) 5) absence of natural selection

Question 40

5 causes of allele frequency changes

Answer 40

1) population shrink 2) mating (nonrandom) 3) mutation 4) movement (migration) 5) natural selection