Evolution of population

Question 1

What are the sources of genetic variation?

Answer 1

Mutation, Recombination, and Hybridization

Question 2

What is mutation

Answer 2

a random change in the DNA of a gene

Question 3

What is recombination

Answer 3

occurs during meiosis which form a new combination of alleles from parents alleles getting arranged in new ways.

Question 4

what is Hybridization

Answer 4

The crossing of two different species.

Question 5

What is a populations gene pool?

Answer 5

all the alleles in a population

Question 6

What are the three types of selection?

Answer 6

Directional, stabilizing, and disruptive

Question 7

What does directional do?

Answer 7

It favors phenotypes of one extreme, shifts graph horizantally.

Question 8

What does stabilizing do?

Answer 8

Favors the intermediate phenotype, extremes are favored against. Stretches graph vertically.

Question 9

What does disruptive do?

Answer 9

Favors both extreme phenotypes, intermediates are favored against. Graph has two peaks like an M.

Question 10

What is the most common kind of selection?

Answer 10

Stabilizing selection

Question 11

What selection most likely results in speciation?

Answer 11

Disruptive

Question 12

Darwins theory of evolution can best be described as…

Answer 12

species arose through gradual transformations

Question 13

What is genetic variation?

Answer 13

It increases the chance of a population surviving and leads to phenotypic varitation

Question 14

What is sexual selection?

Answer 14

when certain traits increase mating success.

Question 15

What type of population is most susceptible to loss of genetic variability as a result of genetic drift

Answer 15

Small Populations

Question 16

What is gene flow?

Answer 16

the movement of alleles between populations, keeps neighboring populations similar, and occurs when individuals join new populations and reproduce.

Question 17

What are the two types of genetic drift

Answer 17

bottleneck and founder

Question 18

What is the bottleneck effect and how does it happen

Answer 18

Occurs when an event drastically reduces population size like a flood or storm.

Question 19

What is the founder effect and how does it happen?

Answer 19

The founding of a small population, it occurs when a few individuals start a new populations.

Question 20

why does genetic drift have negative effects on a population?

Answer 20

Causes a loss of genetic variation and harmful alleles can become more common due to chance

Question 21

What is Hardy-Weinburg equilibrium

Answer 21

a type of model that descirbes populations that are not evolving, biologists use this to study populations.

Question 22

What are the 5 conditions that must be met in order to say a population is in equilibrium?

Answer 22

Very large population no genetic drift, no gene flow, no mutations, random mating: no sexual selection, no natural selection: all traits aid equally in survival

Question 23

What is the equation for H-W

Answer 23

p^2+2pq+q^2

Question 24

Explain the statement “a population is in genetic equilibrium”

Answer 24

The population is not evolving.

Question 25

How do mutations affect genetic equilibrium

Answer 25

they add alleles to the gene pool.

Question 26

What type of things would disrupt gene' tic equilibrium?

Answer 26

mutations, natural selection, sexual selection,gene flow, genetic drift

Question 27

What are the 4 types of isolation

Answer 27

Behavioral, Geographic, temporal, and reproductive

Question 28

What is behaivvoral isolation

Answer 28

Become isolated by differences in courtship rituals or other behaviors.

Question 29

what is geographic isolation

Answer 29

physical barriers dividing population.

Question 30

what is temporal isolation?

Answer 30

When two populations become isolated because they reproduce at different times or patterns.

Question 31

What is reproductive isolation?

Answer 31

Occur between isolated populations, members of different populations cannot mate successfully, the final step to becoming a separate species.

Question 32

What is prezygotic reproductive isolation

Answer 32

Before fertilization, isolation of habitat, differences in breeding season or mating behaviors, in comparability of genitalia.

Question 33

what is postyzygotic isolation

Answer 33

After fertilization, barriers that prevent development, genetic incompatibility, hybrid sterility, and hybrid breakdown.

Question 34

When does reproductive isolation occur?

Answer 34

When a population divides into two groups and the groups interbreed and become two different species.

Question 35

What is sympatric geographic isolation

Answer 35

Can occur within a geographic range of parent population, more common in plants

Question 36

what is allopatric geographic isolation?

Answer 36

through the geographic isolation of a small population from its parent population when geographic isolated populations adapt to different environmental conditions.

Question 37

When does adaptive radiation occur?

Answer 37

when a single ancestral species diversifies into a variety of new species, each adapted to exploit different ecological needs.

Question 38

What are the conditions that must be present in order for adaptive radiation to occur?

Answer 38

Different ecological needs or opportunities arise.

Question 39

What are the various patterns of evolution?

Answer 39

punctuated equilibrium, occur suddenly, long periods of little evolutionary change, through gradual transformations.

Question 40

What is a total and permanent disappearance of a species from earth called?

Answer 40

Extinction

Question 41

What is Microevoluion?

Answer 41

Evolution that occurs within a species due to genetic variation, a struggle to survive and natural selection within that

Question 42

What is macroevolution?

Answer 42

Evolution that occurs between different species

Question 43

What is divergent Evolution

Answer 43

When one species gradually develops into two species and those two species become increasingly different and better adapted to their unique environment.

Question 44

What is convergent evolution?

Answer 44

When two separate species begin to share analogous traits because of shared environment pressures or demands.

Question 45

What is coevolution?

Answer 45

When two separate species evolve independently, but in step with each other