Ch6

Question 1

Population

Answer 1

A group of interacting and potentially interbreeding individuals of the same species.

Question 2

Genetic locus

Answer 2

Location of a specific gene or sequence of DNA on a chromosome

Question 3

Diploid

Answer 3

Individuals that carry 2 alleles at every locus

Question 4

Evolution

Answer 4

Change in allele frequencies from one generation to the next

Question 5

Population genetics

Answer 5

Study of the distribution of alleles within populations and the mechanisms that can cause allele frequencies to change over time.

Question 6

Population allele frequencies do not change if:

Answer 6

-Population is large
-Genotypes do not differ in fitness (no selection)
-No mutation
-Mating is random
-No migration

Question 7

P is the

Answer 7

More common allele

Question 8

q is the

Answer 8

Less common allele

Question 9

Formula for allele frequencies

Answer 9

p + q = 1

Question 10

Formula for genotype frequencies

Answer 10

1 = p² + 2pq + q²

Question 11

p² is the

Answer 11

Homozygous for dominant allele

Question 12

2pq is the

Answer 12

Heterozygous for dominant and recessive alleles

Question 13

q² is the

Answer 13

Homozygous for recessive alleles

Question 14

Hardy-Weinburg

Answer 14

Proof that evolution does not occur in the absence of selection, drift, migration, or mutation.

Question 15

Genetic drift

Answer 15

Evolutionary change due to chance or sampling error (random)

Question 16

Alleles are lost more rapidly in

Answer 16

Small populations

Question 17

Bottleneck:

Answer 17

-Cause genetic drift
-Causes drastic shift in allele frequencies
-Rare alleles are likely to be lost

Question 18

Founder effect (5)

Answer 18

-Occurs when a small population move (from a large population) to colonize a new area
-Only a couple of alleles are brought
-Random change
-Allele frequencies will differ from the original large population
-Is a type of bottleneck

Question 19

Fitness

Answer 19

Reproductive success of an individual with a particular PHENOTYPE

Question 20

Relative fitness

Answer 20

Fitness of a GENOTYPE in comparison to others

Question 21

Darwin’s postulates

Answer 21

1.) There is variation among individuals
2.) Variation os inherited
3.) More individuals are born than will survive to reproduce
4.) Some variants survive and reproduce at a higher rate than others

Question 22

Pleiotropy

Answer 22

Mutation in a single gene affects more than one phenotypic trait

Question 23

Antagonistic pleiotropy

Answer 23

Beneficial effects for one trait but detrimental effects for other traits

Question 24

Natural selection is more effective in

Answer 24

Large populations

Question 25

Selection occurs when

Answer 25

Genotypes differ in fitness

Question 26

Rare alleles are almost always carried in

Answer 26

Heterozygous state

Question 27

Additive alleles

Answer 27

Homozygous condition yields twice the phenotypic effect for the gene as compared to heterozygotes

Question 28

Dominance

Answer 28

Dominant allele masks the presence of recessive allele

Question 29

Mutation rates are

Answer 29

Low About 7.9 bil new mutations per year for humans

Question 30

Negative frequency dependant selection

Answer 30

Common phenotypes are selected against and rare phenotypes are favored

Question 31

Heterozygote advantage

Answer 31

Heterogosity confers greater fitness than homozygotes

Question 32

Most common Non-random mating

Answer 32

Inbreeding

Question 33

Inbreeding depression results in

Answer 33

Reduced fitness

Question 34

Inbreeding causes:

Answer 34

-Increase % of homozygous alleles -NOT a direct mechanism of evolution -Undergo bottlenecks

Question 35

Landscape genetics

Answer 35

Field of research that combines population genetics, landscape ecology, and spatial statistics

Question 36

Population structure (subdivision)

Answer 36

Occurrence of populations that are subdivided by geography, behavior, etc, that prevent individuals from mixing completely. Leads to deviation

Question 37

Genetic drift creates

Answer 37

Genetic distance between populations

Question 38

Subdivided populations show

Answer 38

-Distinct genetic structure -Increase of genetic drift which reduces genetic variation

Question 39

Gene flow (migration)

Answer 39

The transfer of alleles from the gene pool of one population to another. -Can increase genetic variation within populations -Can counteract the loss of alleles due to drift