Unit 3 Week 2

Question 1

coherent understanding of the relationship between natural selection and genetics by 1940s

Answer 1

modern synthesis

Question 2

used to study how selective forces change a population through changes in allele and genotypic frequencies

Answer 2

population genetics

Question 3

rate at which a specific allele appears within a population

Answer 3

allele frequency

Question 4

sum of all alleles in a population

Answer 4

gene pool

Question 5

when alleles spread through every individual of a population, they become _____

Answer 5

fixed

Question 6

allele frequencies within a population change randomly with no advantage to the population over existing allele frequencies

Answer 6

genetic drift

Question 7

event that initiates allele frequency change in an isolated part of the population that’s not part of the original population

Answer 7

founder effect

Question 8

states that population’s allele and genotypic frequencies are inherently stable

Answer 8

Hardy- Weinberg principle of equilibrium

Question 9

frequencies of genotypes

Answer 9

genetic structure

Question 10

populations consisting of two or more variations of particular characteristics

Answer 10

polymorphic

Question 11

distribution of phenotypes among individuals

Answer 11

population variation

Question 12

fraction of phenotype variation that we can attribute to genetic differences among individuals in a population

Answer 12

heritability

Question 13

diversity of alleles and genotypes within a population

Answer 13

genetic variance

Question 14

when scientists breed animals, they try to ______ the genetic variance as much as possible to keep a diverse population of the animal

Answer 14

increase

Question 15

mating of closely related individuals that usually brings together deleterious recessive mutations that can cause abnormalities/ susceptibility to disease

Answer 15

inbreeding

Question 16

when a family of carriers interbreed with each other and the likelihood of two carriers mating and producing diseased offspring is much higher

Answer 16

interbreeding depression

Question 17

a specific quality driving shifts in the genotype of a population

Answer 17

selection pressure

Question 18

large populations are _______ susceptible to the effects of genetic drift

Answer 18

less

Question 19

natural events that kill a large portion of the population magnify genetic drift

Answer 19

bottleneck effect

Question 20

genetic structure changes to match that of the new population’s founding parents

Answer 20

founder effect

Question 21

flow of alleles in and out of a population due to the migration of individuals or gametes

Answer 21

gene flow

Question 22

changes to organism’s DNA that are important drivers of diversity in populations

Answer 22

mutations

Question 23

type of mating that includes mate choice or location based selection

Answer 23

nonrandom mating

Question 24

an individual’s preference to mate with partners who are phenotypically similar to themselves

Answer 24

assortative mating

Question 25

geographic separation between populations that leads to differences in the phenotypic variation between populations

Answer 25

geographical variation

Question 26

given species' populations vary gradually across ecological gradient

Answer 26

cline

Question 27

when gene flow is restricted, individuals will show _______ differences in phenotype along cline

Answer 27

abrupt

Question 28

rate at which specific genotype appears in a population

Answer 28

genotype frequency

Question 29

the requirements of the Hardy Weinberg principle are:

Answer 29

- have random mating among individuals - experiences no mutations in alleles - be under no natural selection - be of infinite population size - have no gene flow