Chapter 7 : The Genetics Of Populations

Question 1

Assortative mating

Answer 1

Mating between members of a population that are more similar - more likely to share the same genotypes

Question 2

Balanced polymorphism

Answer 2

Stable equilibrium that is polymorphic; both alleles are present

Question 3

Balancing selection

Answer 3

Selection that leads to a balanced polymorphism

Question 4

Directional selection

Answer 4

One allele is consistently favored over the other allele. Selection drives allele frequencies in a single direction toward an increasing frequency of the favored allele

Question 5

Disassortative mating

Answer 5

Mating between members of a population that are more dissimilar- more likely to have different genotypes

Question 6

Fecundity

Question 7

Fixation

Answer 7

When an allele becomes fixed

Question 8

Frequency-dependent selection

Question 9

Frequency independent selection

Answer 9

Fitness associated with a trait is not directly dependent on the frequency of the trait in a population

Question 10

Hardy-weinberg equilibrium

Question 11

Hardy-weinberg model

Answer 11

Null model; says what happens to genotype frequencies when natural selection and other important drivers of evolutionary change are not operating.

Question 12

Heterozygote advantage

Answer 12

Example: A1A2 heterozygote has a higher fitness than either the A1A1 or the A2A2 homozygous

Question 13

Identical by descent

Question 14

Inbreeding

Question 15

Inbreeding depression

Answer 15

Continual inbreeding increases the frequency of rare deleterious recessive alleles and homorygotes carrying them

Question 16

Mutation-selection balance

Question 17

Overdominance

Answer 17

Heterozygote advantage

Question 18

Population genetics

Answer 18

How the genotype frequencies in an offspring population are related to the genotype frequencies in a parental population

Question 19

Selection coefficients

Answer 19

Parameter that describes the fitness reduction

Question 20

Underdominance

Answer 20

Reverse of overdominance; the A1A2 heterozygote has a lower fitness than either the A1A1 or A2A2 genotype

Question 21

Wright’s f-statistic

Answer 21

Quantifies the amount of inbreeding in a population. Tends to be higher in small populations.