Deck 4: Population Genetics

Question 1

In the Hardy-Weinberg formula,2pq refers to the frequency of:

A)AA
B)Aa
C)aa
D)AA + aa

Answer 1

Aa

Question 2

The equation p² +2pq + q² =1 is the algebraic expression for:

A)genetic equilibrium
B)natural selection
C)genetic drift
D)assortative mating

Answer 2

genetic equilibrium

Question 3

Genetic equilibrium is maintained in a gene pool under ideal conditions.This equilibrium is disturbed by:

A)nonrandom mating
B)mutation
C)genetic drift
D)all of the above

Answer 3

all of the above

Question 4

Genetic equilibrium refers to:

A)a population with equal amounts of dominant and recessive alleles
B)a situation in which there is no change in the frequency of alleles in a population
C)individuals who are the most fit in a population
D)a population in which matings are completely random

Question 5

If a population is in genetic equilibrium,then p² + ____ + q² =1.

A)2pq
B)pq
C)1
D)p²q²

Question 6

If 36 percent of the individuals in a population have the genotype aa,then the frequency of the allele a is:

A)0.032
B)0.32
C)0.40
D)0.60

Question 7

The smallest natural reproductive population is the:

A)deme
B)species
C)subspecies
D)genus

Question 8

The genotype of a population is known as the:

A)genetic load
B)allele load
C)gene pool
D)allele pool

Question 9

A condition which must be assumed for the state of genetic equilibrium is:

A)small population size
B)low mutation rate
C)random mating
D)differential fertility

Question 10

Biological evolution can be defined as:

A)changes in gene frequencies in response to specific selective pressures
B)changes in gene frequencies as a result of changes in mutation rates
C)changes in gene frequencies as a result of genetic drift
D)any change in gene frequencies from one generation to the next

Question 11

That which is evolving is the:

A)individual
B)family
C)lineage
D)reproductive population

Question 12

If a population is in genetic equilibrium,the frequency of alleles will:

A)remain constant
B)change only slightly
C)show an increase in dominant alleles
D)show an increase in recessive alleles

Question 13

If a population is in genetic equilibrium,then p² +2pq + q² =:

A)0
B)½
C)1
D)10

Question 14

Genetic equilibrium is maintained in a gene pool under ideal conditions.This equilibrium is disturbed by:

A)gene flow
B)random mating
C)lack of natural selection
D)all of the above

Question 15

A population is not evolving if the allele frequencies remain constant,a situation termed:

A)natural selection
B)genetic equilibrium
C)population equilibrium
D)gene pool constancy

Question 16

Biological evolution can be defined as a change in the frequency of alleles in the:

A)genotype
B)gene pool
C)phenotype
D)none of the above

Question 17

Statistically,how often will a given real-world population be in a state of genetic equilibrium?

A)100 percent
B)80 percent
C)25 percent
D)0 percent
E)impossible to determine

Question 18

Successful reproduction requires:

A)successful sexual behavior
B)normal development of the fetus
C)production of offspring capable of reproducing in turn
D)all of the above

Question 19

The largest natural reproductive population is the:

A)deme
B)species
C)subspecies
D)genus

Question 20

The equation p² +2pq + q² =1 is the algebraic expression of a principle developed by:

A)Darwin and Wallace
B)Mendel and Weismann
C)Hardy and Weinberg
D)Wright and Dobzhansky

Question 21

Is the above population in genetic equilibrium?

A)no;it is far from genetic equilibrium
B)yes;observed and expected frequencies are the same
C)the population is close to being in genetic equilibrium with the expected and observed phenotypic frequencies being close together

Question 22

If allele A has a frequency of 0.70 and allele a has a frequency of 0.30,then the frequency of the heterozygote genotype would be:

A)0.42
B)0.36
C)0.21
D)0.09

Question 23

Microevolution is an(n):

A)increase in complexity over time
B)change in physical appearance over time
C)change in allele frequencies over time
D)progress toward a more humanlike condition over time

Question 24

If in a population 25 percent are nontasters (tt),the frequency of the recessive allele would be:

A)0.05
B)0.10
C)0.25
D)0.50

Question 25

A new mutation is most likely to be:

A)deleterious
B)neutral
C)beneficial
D)all of the above

Question 26

Although the mutation rate varies from gene to gene,most estimates for the number of new mutations that occur in sex cells for a given gene are about 2-12 in every _____ gametes:

A)100
B)1,000
C)100,000
D)100,000,000

Question 27

A new mutation may be:

A)deleterious
B)neutral
C)beneficial
D)all of the above

Question 28

Mutations may result from:

A)radiation
B)certain chemicals and drugs
C)some viruses
D)all of the above

Question 29

If the frequency of a recessive allele is 0.7,it follows that the frequency of the dominant allele would be:

A)0.30
B)0.40
C)0.60
D)0.90

Question 30

A lethal allele is defined as:

A)an allele that destroys its complementary allele
B)an allele that,when expressed,causes death through natural causes / old age
C)an allele that,when expressed,causes death before reproductive age
D)any allele that causes a disease

Question 31

If in a population 36 percent of the individuals tested are nontasters (tt),what is the frequency of the allele T?

A)0.36
B)0.40
C)0.48
D)0.60

Question 32

Mutation occurs:

A)to fulfill a need
B)randomly
C)only because of radiation
D)in only about one out of100 persons

Question 33

Mutations caused by human-made substances or activities are:

A)spontaneous mutations
B)induced mutations
C)of no evolutionary significance
D)all of the above

Question 34

A mechanism for evolutionary change is:

A)mutation
B)genetic drift
C)gene flow
D)all of the above

Question 35

An error at a particular point on the DNA molecule is referred to as a:

A)point mutation
B)genetic drift
C)chromosome mutation
D)allele mutation

Question 36

A mutagen is:

A)A factor that is capable of causing mutations
B)A neutral mutation
C)A beneficial mutation
D)A harmful mutation

Question 37

The term which refers to the totality of recessive lethal alleles in a population is:

A)mutation index
B)gene pool
C)genetic load
D)lethal load

Question 38

In the above population what are the frequencies of the genotypes AA,Aa,and aa?

A)0.68,0.92,0.40
B)0.25,0.50,0.25
C)0.33,0.50,0.17
D)0.34,0.46,0.20

Question 39

In a population,170 people are AA,230 are Aa,and 100 are aa.The frequency of the alleles A and a are:

A)0.25 and 0.75
B)0.34 and 0.20
C)0.57 and 0.43
D)0.66 and 0.34

Question 40

H.J.Muller is known for his research on the:

A)relationship between mutations and narcotic drugs
B)causes of spontaneous mutation
C)relationship between induced mutation and X rays
D)sequencing of genes on the chromosome

Question 41

Gene flow can result in:

A)alteration of the effects of genetic drift
B)mutation
C)homogenization of populations
D)a and c

Question 42

A high frequency of consanguineous matings most likely would result in an increase in the frequency of:

A)homozygous genotypes
B)heterozygous genotypes
C)recessive alleles
D)none of the above

Question 43

An earthquake occurs and destroys 95 percent of a specific population.The surviving population displays gene frequencies that are different from those of the original population.This is likely due to:

A)new spontaneous mutations adaptive to the possibilities of more earthquakes
B)sampling error
C)an increased mutation rate
D)new selective pressures that arise after the earthquake

Question 44

Consanguineous mating within a population would tend to:

A)decrease the homogeneity of that population
B)increase the homogeneity of that population
C)increase the heterogeneity of that population
D)have no effect on the gene pool

Question 45

Cross-cousin preferential marriage is a form of:

A)consanguineous mating
B)assortative mating
C)random mating
D)none of the above

Question 46

Which of the following is true about mutations?

A)While most mutations do not confer any advantage to a population,over time they provide for increased variability.
B)Modern medical technology has significantly reduced the number of new mutations in the human population.
C)Microevolution is the accumulation of mutations over time.
D)New mutations occur in order to increase the probability of a population surviving in a particular habitat.

Question 47

Gene flow refers to:

A)the tendency for a gene to gradually move (flow)from one position on a chromosome to another
B)people migrating to a new geographic area
C)the process by which alleles from one gene pool move into another gene pool
D)the movement of people across oceans or other large bodies of water

Question 48

A small group of individuals who colonize a new area most likely will not represent a random sample of alleles of the population from which they came.This is the concept of:

A)genetic drift
B)assortative mating
C)founder principle
D)nonrandom mating

Question 49

An example of assortative mating would be:

A)people mating at random
B)tall people tending to mate with tall people
C)people tending to mate with their first cousins
D)all of the above

Question 50

The phenomenon described in the above question is called:

A)balanced polymorphism
B)population bottlenecking
C)generation gap
D)gene flow

Question 51

Homozygosity:

A)increases when people of similar rather than diverse ancestry mate
B)increases when people of diverse ancestry mate
C)is unaffected by mating patterns
D)is not permitted in the United States

Question 52

The process of genetic drift is most significant in a population which is:

A)small
B)large
C)under stress
D)primitive

Question 53

If a population of early humans was reduced from 50,000 to 500 individuals because of a natural disaster,we might find that the resulting and future populations show,when compared with the original population:

A)no changes in gene frequencies
B)greater genotypic and phenotypic variation
C)less genotypic and phenotypic variation
D)further reduction in population size leading to extinction

Question 54

Consanguineous mating may be the result of:

A)assortative mating
B)preferential marriage
C)a small population
D)b and c

Question 55

Those more likely to be responsible for gene flow are:

A)women
B)men
C)both sexes equally

Question 56

In tribal societies trust is placed with family members as opposed to those outside the family.This extends to marriage,where the most desirable marriages are with relatives.In one society on the northwest coast of British Columbia the most desirable marriage is between a boy and his mother's brother's daughter,which makes his mother's brother (maternal uncle)his father-in-law.This type of mating is called:

A)assortative mating
B)incest
C)consanguineous mating
D)random mating

Question 57

Migration refers to:

A)a long-term movement to a new area
B)movement to a new area,including a short trip
C)a high death rate due to natural selection in new areas
D)rapid evolutionary change

Question 58

Sampling error includes the phenomenon of:

A)founder principle
B)nonrandom mating
C)genetic drift
D)a and c

Question 59

Assortative mating occurs when:

A)people with certain phenotypes mate at nonrandom frequencies
B)siblings or other very closely related people mate
C)people mate at random with regard to phenotype
D)none of the above

Question 60

The United States is a country of immigrants.Newly arrived immigrants tend to settle near one another for social comfort and support,thus forming small,semi-isolated populations.The frequencies of the ABO blood types in these populations are often very different from the population of the mother country.This is due to the fact that:

A)the small size of the immigrant population is not a random sample of the mother population
B)mutation rates are higher in the United States
C)natural selection quickly produces changes in the frequencies of ABO blood types
D)none of the above

Question 61

Not all matings are equally fertile.This is part of:

A)genetic equilibrium
B)genetic drift
C)genetic load
D)natural selection

Question 62

Although natural selection operates upon the phenotype:

A)only dominant alleles are passed on to the next generation
B)new physical traits caused by environmental stresses can be passed on to the next generation
C)only beneficial alleles are passed on to the next generation.
D)none of the above

Question 63

Matching Questions
match each portion of the Hardy-Weinberg equation with the genotype frequency that it refers to:

-p²

A)Aa
B)aa
C)AA

Question 64

Natural selection refers to:

A)mutations
B)genetic equilibrium
C)nonrandom mating
D)none of the above

Question 65

Matching Questions
match each portion of the Hardy-Weinberg equation with the genotype frequency that it refers to:

-.2pq

A)Aa
B)aa
C)AA

Question 66

The unusual gene frequencies among the Amish can be explained on the basis of:

A)the founder principle
B)genetic drift
C)consanguineous mating
D)all of the above

Question 67

Epigenetic changes refers to:

A)nonbiological changes in a person's phenotype such as when someone dyes their hair
B)biological changes that do not involve changes in the genetic code
C)major environmental changes such as global warming
D)Changes in the patterns of gene flow for a specific population

Question 68

Matching Questions
match the term with its definition:

-sampling error

A)mutation
B)consanguineous mating
C)genetic drift
D)natural selection

Question 69

Describe the state of genetic equilibrium.How common is genetic equilibrium in natural populations?

Question 70

Matching Questions
match the term with its definition:

-mating with a relative

A)mutation
B)consanguineous mating
C)genetic drift
D)natural selection

Question 71

"Differential rates of mortality and fertility" defines the term:

A)genetic drift
B)mutation
C)differential migration
D)natural selection

Question 72

Matching Questions
match the term with its definition:

-differential fertility and mortality

A)mutation
B)consanguineous mating
C)genetic drift
D)natural selection

Question 73

What are the purposes of the Hardy-Weinberg formula?

Question 74

Matching Questions
match each portion of the Hardy-Weinberg equation with the genotype frequency that it refers to:

-q²

A)Aa
B)aa
C)AA

Question 75

What is meant by the term genetic load? What facts bring about an increase in the genetic load and what are some of the consequences of this increase?

Question 76

Write a concise definition of evolution in genetic terms.

Question 77

Epigenetics might explain why identical twins:

A)are always biologically exactly the same
B)always behave exactly the same
C)have the same genetic code,but might show phenotypic differences
D)are always the same sex.

Question 78

Matching Questions
match the term with its definition:

-alteration of DNA molecule

A)mutation
B)consanguineous mating
C)genetic drift
D)natural selection

Question 79

The probability is that a genetic disease with the highest carrier rate among members of group A will occur:

A)at the lowest rate if members of group A mate only with other members of group A
B)at a lower rate if members of group A mate outside of the group as opposed to mating within it
C)at a higher rate if members of group A mate outside of the group as opposed to mating within it
D)at about the same rate as any other group,since carrier rates do not directly affect resultant phenotypes

Question 80

In genetic terms,what is a population? How can the phenotype and genotype of a population be described?