Question 1

A new predator is introduced to an area that can feed on any millipedes shorter than 200 millimeters. No millipedes that live in that area are longer than 15 millimeters. What will happen?

Accepted Answer

A)   Disruptive selection will favor 15-millimeter-long millipedes.
B)   Directional selection will favor predators that consume the smallest millipedes.
C)   Millipedes will necessarily evolve to avoid the predator.
D)   The millipedes will necessarily mutate to be longer.
E)   All millipedes will be potential prey. E

Question 2

Which of the following can affect a small, endangered population so severely that it goes extinct?

Accepted Answer

A)   Artificially adding new genes
B)   Matings with a closely related species
C)   Sexual selection
D)   Increased mating opportunities
E)   Lost alleles and/or low genetic diversity E

Question 3

The gene pool for a particular population is made up of

Accepted Answer

A)   all the alleles for a certain trait in a given individual.
B)   all the genes for a certain trait that occur in the population.
C)   all the genes that occur in the population.
D)   the sum of all the homozygous individuals in the population.
E)   the sum of all the heterozygous individuals in the population. C

Question 4

The fish in a certain population average 10 millimeters in length. Imagine that a population of predatory birds arrives in the area, but they cannot eat fish longer than 15 millimeters. After a decade, if the fish average 14 millimeters in length, what probably happened?

Accepted Answer

A)   The presence of the predator caused mutations for larger fish to occur.
B)   The longer fish survived and produced more offspring than shorter fish.
C)   There was stabilizing selection for fish length.
D)   The fish and the predator coevolved.
E)   There was disruptive selection for fish length.

Question 5

What conditions are necessary for a population to be at equilibrium?

Accepted Answer

The answer of What conditions are necessary for a population...

Question 6

In a certain species of salmon, some adult males are extremely large whereas other adult males are very small, compared to the females. There are no intermediate-sized adult males in the population. This is probably the result of

Accepted Answer

A)   disruptive selection.
B)   artificial selection.
C)   directional selection.
D)   stabilizing selection.

Question 7

When different species closely interact for an extended period of time and develop new adaptations in response to each other, it is called

Accepted Answer

A)   gene flow.
B)   genetic drift.
C)   sexual selection.
D)   stabilizing selection.
E)   coevolution.

Question 8

Which of the following can evolve?

Accepted Answer

A)   Individuals
B)   Populations
C)   Communities
D)   Genes

Question 9

Which trait is the best example of an adaptation?

Accepted Answer

A)   A mutation resulting in a heat-resistant enzyme in a bacterium living in a hot spring
B)   A shorter neck in a giraffe that lives in an area with many rival males and tall trees
C)   A longer tongue in an insect-eating mammal that feeds on insects that live in shallow burrows
D)   A new mutation that confers Tay-Sachs disease in humans
E)   A mutation resulting in weak branches in a species of tree that lives in windy regions

Question 10

A population with__________ is at risk for extinction.

Accepted Answer

The answer of A population with__________ is at risk for...

Question 11

In a population, the most common phenotype represents the dominant allele.

Accepted Answer

A) True 
 B)False

Question 12

Suppose that the only remaining population of a certain reptile species lives on an African mountain and that there is no migration out of this large but isolated population. Which of the following describes the most likely future of this reptile population?

Accepted Answer

A)   Evolution will continue because of mutations, assortative mating, and genetic drift.
B)   The population will survive only as long as the environment remains constant.
C)   The population will go extinct after a few generations because of inbreeding.
D)   Evolution will promptly cease.
E)   The bottleneck effect will cause major evolutionary changes in the isolated population.

Question 13

Organisms that have the greatest reproductive success are considered the most evolutionarily fit.

Accepted Answer

A) True 
 B)False

Question 14

Imagine that one of the original four mice that escape from a research lab is blind due to a genetic defect. If the escaped mouse breeds and most of the mice born in subsequent generations are blind from birth, this is most likely a case of

Accepted Answer

A)   the founder effect.
B)   artificial selection.
C)   selective mutation.
D)   natural selection.
E)   an equilibrium population.

Question 15

Gene flow

Accepted Answer

A)   prevents migration of individuals into other populations.
B)   negates the influence of evolution on a population.
C)   limits evolutionary fitness.
D)   can spread certain alleles throughout a species.
E)   isolates populations from one another.

Question 16

Evolution occurs in_______ .

Accepted Answer

The answer of Evolution occurs in_______ ....

Question 17

Genetic drift is more common in large populations than in small populations.

Accepted Answer

A) True 
 B)False

Question 18

Which of the following occurs due to chance events that change the allele frequencies in small populations?

Accepted Answer

A)   Gene flow
B)   Genetic drift
C)   Sexual selection
D)   Stabilizing selection
E)   Coevolution

Question 19

When one species evolves a new phenotypic feature and another species evolves new adaptations in response, it is called

Accepted Answer

A)   gene flow.
B)   genetic drift.
C)   sexual selection.
D)   stabilizing selection.
E)   coevolution.

Question 20

In the context of evolution, equilibrium means

Accepted Answer

A)   no individuals move into or out of the population.
B)   equal numbers of males and females.
C)   equal numbers of all alleles.
D)   no change in allele frequency.
E)   no change in population size.

Exam 16: How Populations Evolve

A new predator is introduced to an area that can feed on any millipedes shorter than 200 millimeters. No millipedes that live in that area are longer than 15 millimeters. What will happen?

Which of the following can affect a small, endangered population so severely that it goes extinct?

The gene pool for a particular population is made up of

The fish in a certain population average 10 millimeters in length. Imagine that a population of predatory birds arrives in the area, but they cannot eat fish longer than 15 millimeters. After a decade, if the fish average 14 millimeters in length, what probably happened?

What conditions are necessary for a population to be at equilibrium?

In a certain species of salmon, some adult males are extremely large whereas other adult males are very small, compared to the females. There are no intermediate-sized adult males in the population. This is probably the result of

When different species closely interact for an extended period of time and develop new adaptations in response to each other, it is called

Which of the following can evolve?

Which trait is the best example of an adaptation?

A population with__________ is at risk for extinction.

In a population, the most common phenotype represents the dominant allele.

Suppose that the only remaining population of a certain reptile species lives on an African mountain and that there is no migration out of this large but isolated population. Which of the following describes the most likely future of this reptile population?

Organisms that have the greatest reproductive success are considered the most evolutionarily fit.

Imagine that one of the original four mice that escape from a research lab is blind due to a genetic defect. If the escaped mouse breeds and most of the mice born in subsequent generations are blind from birth, this is most likely a case of

Gene flow

Evolution occurs in_______ .

Genetic drift is more common in large populations than in small populations.

Which of the following occurs due to chance events that change the allele frequencies in small populations?

When one species evolves a new phenotypic feature and another species evolves new adaptations in response, it is called

In the context of evolution, equilibrium means