Question 1

Select the phrases that can be associated with intersexual selection

Accepted Answer

A)  mate choice
B)  males fighting males to win a territory
C)  peahens choosing peacocks with greater number of eyespots in their tail feathers
D)  sexual selection within a sex A,C

Question 2

In some instances environmental change causes a situation where one phenotype is favored for a period of time,and then a different phenotype is favored.This oscillating selection causes

Accepted Answer

A)  the maintenance of genetic variation in the population.
B)  elimination of rarer genotypes because of uneven selection.
C)  an increase in point mutations.
D)  high population increase to maintain phenotypic variation.
E)  extinction of the population. A

Question 3

Animals that select mates that are phenotypically similar will have ________ when compared with Hardy-Weinberg predictions.

Accepted Answer

A)  fewer homozygotes
B)  less natural selection
C)  more heterozygotes
D)  more homozygotes.
E)  more mutations D

Question 4

There are more than 30 blood group genes in humans,in addition to the ABO locus.This increases ________ in human populations.

Accepted Answer

A)  genetic variability
B)  homozygosity
C)  selective mating
D)  gene flow
E)  founder effects

Question 5

You spray your kitchen with an insecticide to kill the cockroaches.A few survive and reproduce,producing a large healthy population in a few generations that all have similar genetic backgrounds.This is an example of ________

Accepted Answer

A)  mutation.
B)  migration.
C)  genetic drift.
D)  assortative mating.
E)  bottleneck effect.

Question 6

The key point in Darwin's proposal is that the ________ imposes the conditions that determine the direction of selection.

Accepted Answer

A)  parent
B)  gene
C)  individual
D)  environment

Question 7

A population of lizards lives in a rocky area next to a desert.Some lizards are light colored and blend into the sand.Others are dark and blend into the rocks.What may happen to this population of lizards over time?

Accepted Answer

A)  They may evolve into two separate species as a result of disruptive selection.
B)  They may evolve into two separate species as a result of directional selection.
C)  They may remain one species as a result of disruptive selection.
D)  They may remain one species as a result of directional selection.
E)  They may remain one species as a result of stabilizing selection.

Question 8

The presence of the disease sickle cell anemia illustrates that natural selection does not always eliminate ________ alleles.

Accepted Answer

A)  dominant
B)  recessive
C)  polymorphic
D)  neutral

Question 9

Investigate sexual selection by completing the sentences.

Accepted Answer

The answer of Investigate sexual selection by completing the sentences....

Question 10

A population of flowers is in Hardy-Weinberg equilibrium with an allele frequency for white flowers (w)of 40%.What percentage of the flowers will have the colored or dominant phenotype?

Accepted Answer

A)  16%
B)  25%
C)  40%
D)  60%
E)  84%

Question 11

Investigate the effects of the costs of reproduction by completing the sentences.

Accepted Answer

The answer of Investigate the effects of the costs of...

Question 12

An insect population that becomes resistant to a commonly used insecticide is an example of ________.

Accepted Answer

A)  natural selection
B)  genetic drift
C)  disruptive selection
D)  a founder effect
E)  gene flow

Question 13

Moths that can evade a bat's echolocation have ________ that increase their likelihood of survival and reproduction.

Accepted Answer

A)  genes
B)  fitness
C)  mutations
D)  adaptations
E)  selection

Question 14

By evaluating and selecting mates with superior qualities,an animal can increase its

Accepted Answer

A)  reproductive success.
B)  learning.
C)  competitive strategies.
D)  foraging efficiency.
E)  length of life.

Question 15

The percentage of different colored water boatmen eaten by fish were graphed relative to the frequency of that color in the population.Based on the graph,a population of water boatmen would ________

Accepted Answer

A)  lose rare genotypes.
B)  have no variation in genotype frequencies.
C)  increase in rare genotypes.
D)  increase in size.
E)  decrease in genetic variability.

Question 16

Being born with extra fingers on a hand is called polydactyly.This is more common in some populations in North America than others due to ________.

Accepted Answer

A)  a founder effect because their ancestors from Europe carried the alleles
B)  an increase in mutation rate in these populations
C)  random mating with other populations in North America
D)  natural selection in favor of extra fingers in these populations
E)  migration of people with multiple fingers out of the population

Question 17

In the graph above,how can the change in infant mortality be explained as birth weight increases from 2 to 7 pounds?

Accepted Answer

A)  A larger baby will have more developed organs and thus have greater fitness.
B)  A baby closer to 7 pounds will not be able to be delivered safely and thus have higher mortality.
C)  A baby closer to 7 pounds will have more developed organs and thus have higher mortality.
D)  A baby closer to 7 pounds will have more developed organs and thus have lower mortality.
E)  A baby closer to 2 pounds will not be able to be delivered safely and thus have lower mortality.

Question 18

About 80% of the alleles present in thoroughbred horses can be dated back to 31 known ancestors from the late eighteenth century.As a result,one would expect ________

Accepted Answer

A)  low rates of mutation.
B)  many polymorphic alleles.
C)  little variation in physiology and behavior.
D)  Hardy-Weinberg equilibrium.
E)  random mating.

Question 19

In early ancestors of the modern giraffe,longer necks allowed animals to reach higher tree branches as food.This would lead to ________ in the ancestral giraffe population.

Accepted Answer

A)  directional selection
B)  stabilizing selection
C)  disruptive selection
D)  sexual selection
E)  genetic drift

Question 20

Cheetahs have been through a genetic bottleneck; evidence for this is that

Accepted Answer

A)  little natural selection occurs in this species.
B)  the body is long,thin,and graceful.
C)  there is very little genetic variability.
D)  these cats are members of an endangered species.
E)  they originally came from small areas of Africa.

Exam 20: Genes Within Populations