CH 23

Question 1

Microevolution

Answer 1

-evolutionary change below the species level
-change in the allele frequencies in populations over generations

Question 2

Genetic variation sources 1

Answer 2

-formation of new alleles
-arise via mutation

Question 3

Genetic variation sources 2

Answer 3

-altering gene number or position
-delete, disrupts, or rearrange

Question 4

Genetic variation sources 3

Answer 4

-rapid reproduction

Question 5

Genetic variation sources 4

Answer 5

-sexual reproduction
-unique combination of alleles

Question 6

average heterozygosity

Answer 6

-measure of genetic variability within a population

Question 7

Hardy Weinberg

Answer 7

-no mutations
-random mating
-no natural selection
-large population size
-no gene flow

Question 8

what can alter gene flow

Answer 8

-genetic drift
-founder effect
-bottleneck effect

Question 9

genetic drift

Answer 9

-no alleles in or out

Question 10

founder effect

Answer 10

-small group establishes a new population whose gen pool differs from source population

Question 11

bottleneck effect

Answer 11

-severe drop in population size

Question 12

Non-sexual selection

Answer 12

-directional selection
-disruptive selection
-stabilizing selection

Question 13

directional selection

Answer 13

-occurs when conditions favor individuals exhibiting one extreme of a phenotype
-one side of bell curve

Question 14

disruptive selection

Answer 14

-occurs when conditions favor individuals at both extremes of a phenotype
-both sides outside bell curve

Question 15

stabilizing selection

Answer 15

-acts against both extreme phenotypes and favors intermediate varians
-within/smaller than bell curve

Question 16

sexual selection

Answer 16

-intersexual selection
-intrasexual selection

Question 17

intrasexual selection

Answer 17

-selection within the same sex
-individuals of one sex compete directly for mate of opposite sex
-mainly males

Question 18

intersexual selection

Answer 18

-mate choice
-individuals of one sex (mainly female) are choosy in selecting their mates from the other sex

Question 19

balancing selecton

Answer 19

-frequency-dependent selection
-heterozygote advantage

Question 20

frequency-dependent selection

Answer 20

-the fitness of a phenotype depends on how common it is in the population

Question 21

heterozygote advantage

Answer 21

-individuals who are heterozygous at a particular locus have a greater fitness than do both kinds of homozygous