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19 terms

chapter 25

population genetics
STUDY
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True or False:
All genetic drift arises from sampling errors and chance
True
True or false:
A population may be in Hardy-Weinberg equilibrium for one locus but not for others.
True
True or false:
If an allele is "fixed" in a population, it has a frequency of 1.0.
True
True or false:
Inbreeding results in an increase in the frequency of heterozygotes compared to the results of random mating.
False
True or false:
Genetic variation must exist within a population before evolution can take place.
True
True or false:
Allelic frequencies within populations are affected by dominance and recessiveness.
False
True or false:
Natural selection is defined as the differential reproduction of genotypes.
True
True or false:
Overdominance refers to the lack of expression of recessive phenotypes.
False
True or false:
Genetic bottlenecks are a type of founder effect.
True
True or false:
Genetic differences in large, randomly breeding populations remain constant if migration occurs.
False
Which of the following is NOT an example of nonrandom mating?
a. positive assortative mating
b. inbreeding
c. outbreeding
d. panmixis
e. negative assortative mating
d. panmixis
The probability that two alleles are identical by descent is the _____

a. coalescent
b. inbreeding coefficient
c. panmictic constant
d. outcrossing rate
e. relatedness
b. inbreeding coefficient
Rapid changes in allelic frequencies by __ take place in populations that are __ .
a. mutation
b. evolving
c. inbred
d. small
e. genetic drift
e. genetic drift
d. small
Migration tends to _ genetic variation between subpopulations and _ genetic variation within each subpopulation.
a. increase
b. not change
c. reduce
d. standardize
e. invert
c. reduce
a. increase
A Mendelian population is defined by individuals
a. interbreeding.
b. inbreeding.
c. evolving.
d. living in close proximity.
e. migrating.
a. interbreeding
Which of the following evolutionary forces does NOT change allele frequencies?
a. nonrandom mating
b. mutation
c. selection
d. drift
e. migration
a. nonrandom mating
. Any change in a population from Hardy-Weinberg equilibrium can be defined as ______.
a. mutation
b. genetic equilibrium
c. migration
d. evolution
e. natural selection
d. evolution
Matching:

27. evolution
28. inbreeding coefficient
29. genetic drift
30. gene pool
31. migration
32. mutation
33. negative directional selection

a. All genetic information within a Mendelian population
b. The mean trait value decreases from one generation to another
c. Any change in allele frequencies within a population
d. Probability of alleles being identical by descent
e. Alleles may disappear from the population simply by chance
f. Movement of genes
g. Generation of new alleles
c, d, e, a, f, g, b
Matching:


Phenomenon
34. population bottleneck
35. gene flow between two island populations
36. mutation
37. genetic drift
38. negative directional selection

Effect
a. Allele frequencies become more similar across populations
b. Generation of new alleles changes allele frequencies very slowly
c. Alleles may disappear from the population simply by chance
d. Allele frequencies do not change
e. The mean trait value decreases from one generation to another
c, a, b, c, e