Unit 7

Question 1

gene pool

Answer 1

sum of all genes in a population at any one time

Question 2

allele

Answer 2

copy of a gene, humans have 2 alleles for each gene

Question 3

microevolution

Answer 3

change in genetic structure of a population from one generation to the next

Question 4

3 random causes of microevolution

Answer 4

genetic drift, gene flow, mutation

Question 5

2 non-random causes of microevolution

Answer 5

non-random mating, natural selection

Question 6

genetic drift

Answer 6

changes in gene pool of a population due to random chance of events

Question 7

bottleneck effect

Answer 7

significant reduction of the original population size due to natural disaster or overexploitation

Question 8

founder effect

Answer 8

very small number of individuals from original population colonize a new habitat

Question 9

gene flow

Answer 9

addition or loss of alleles from a populations gene pool due to the migration of fertile individuals or gametes (reduces genetic differences between populations)

Question 10

mutation

Answer 10

change in nucleotide sequence of organisms DNA

Question 11

non-random mating: inbreeding

Answer 11

mating within family (increases homozygotes)

Question 12

non-random mating: assortative maing

Answer 12

individuals select partners that are like themselves

Question 13

natural selection

Answer 13

a process where organisms with traits better suited to their environment are more likely to survive and reproduce, passing on their traits

Question 14

balances polymorphism

Answer 14

ability of natural selection to maintain diversity in a population

Question 15

heterozygote advantage

Answer 15

natural selection favors heterozygous condition over homozygous conditions

Question 16

frequent dependent selection

Answer 16

reproductive success of any one morph depends on the frequency of that particular morph in the population

Question 17

geographical variation

Answer 17

change in location leads to genetic variation between populations

Question 18

diploidy

Answer 18

permits heterozygotes to maintain presence of harmful recessive alleles in the population

Question 19

How can we determine genetic structure of a population?

Answer 19

using the Hardy-Weinberg equilibrium

Question 20

True or false: the hardy Weinberg equilibrium is very unlikely in nature

Answer 20

true

Question 21

what does p squared represent

Answer 21

frequency of homozygous dominant genotype

Question 22

what does p represent

Answer 22

frequency of the dominant allele

Question 23

what does p squared + 2pq

Answer 23

frequency of the dominant allele

Question 24

what does q represent

Answer 24

frequency of recessive allele

Question 25

what does 2pq represent

Answer 25

frequency of heterozygous genotype

Question 26

what does q squared represent

Answer 26

frequency of homozygous recessive genotype or frequency of recessive phenotype

Question 27

Lamarck's theory of evolution: Use and disuse

Answer 27

traits that give an organism an advantage become bigger + stronger

Question 28

Lamarck's theory of evolution: Inheritance of acquired characteristics

Answer 28

organisms could develop traits needed to better survive in their environment

Question 29

August Weismann's experiment

Answer 29

mated mice whose tails had been cut off, no offspring inherited tailless trait

Question 30

inherited variation sources

Answer 30

random mutation + sexual reproduction

Question 31

Darwinian fitness

Answer 31

contribution an individual makes to the next generation

Question 32

relative fitness

Answer 32

contributions of one genotype compared to alternative genotypes

Question 33

selective pressure

Answer 33

factor that dictates what phenotype is selected for

Question 34

stabilizing selection

Answer 34

selects intermediate phenotypes

Question 35

directional selection

Answer 35

favors phenotype of one extreme

Question 36

diversifying selection

Answer 36

favors phenotypes of opposite extremes