bz 110 exam 2 review Questions with
Correct Answers
Natural selection acts on individual __________, not on individual genes. -
ANSWERSphenotypes
The total genetic makeup of a population is the _______. - ANSWERSgene pool
One of the assumptions of the Hardy-Weinberg theorem is that _______. -
ANSWERSmating within the population is random
One of the assumptions of the Hardy-Weinberg theorem is that _______. -
ANSWERSmutations must not occur or a mutational equilibrium must exist
The work of Peter and Rosemary Grant, on morphological changes in the bills of
Galápagos finches, shows that evolution can be _______. - ANSWERSrapid
Assuming the conditions set by Hardy-Weinberg equilibrium, if the frequency of
phenotype A is 96%, the frequency of A in the next generation would be _______. -
ANSWERS96%
When the Hardy-Weinberg equilibrium is achieved, evolution _______. -
ANSWERSdoes not occur
Which of the following is not an assumption of the Hardy-Weinberg theorem? -
ANSWERSNatural selection is acting on the population.
When natural selection favors certain phenotypes in a population, the population is
responding to _______. - ANSWERSselection pressure
__________ selection may occur when a phenotype at one extreme of a distribution is
at a disadvantage. - ANSWERSDirectional
When individuals of an intermediate phenotype are at a relative disadvantage within the
population, __________ selection is occurring. - ANSWERSdisruptive
A form of natural selection that occurs when both phenotypic extremes are selected
against is __________ selection. - ANSWERSstabilizing
When chance events influence the frequency of alleles within a population, __________
has occurred. - ANSWERSgenetic drift
, Genetic drift is most likely to have noticeable effects in _______. - ANSWERSsmall,
isolated populations
Overhunting of the elephant seal dramatically reduced its numbers in the 1800s. The
population has since increased, but due to the _____________ effect, its genetic
diversity is still very low. - ANSWERSbottleneck
Mutations of an organism's DNA are _______. - ANSWERSsometimes silent and
carried through generations with no ill effects
In a human population carrying the gene for sickle-cell anemia, and exposed to malaria,
several genotypes persist in a _______. - ANSWERSbalanced polymorphism
The biological definition of a __________ is a group of populations in which genes are
actually, or potentially, exchanged through interbreeding. - ANSWERSspecies
A requirement for speciation is that subpopulations _______. - ANSWERSbecome
reproductively isolated from one another
Geographic isolation can lead to speciation, and when it does, the speciation is called
_______. - ANSWERSallopatric
Parapatric speciation may occur among small, local populations called _______. -
ANSWERSdemes
An animal's __________ includes all of the biotic and abiotic characteristics of the area
in which the animal lives. - ANSWERShabitat
When an abiotic factor is out of the range of tolerance for an animal, it becomes a/an
_______. - ANSWERSlimiting factor
On a survivorship curve, the Y axis records _______. - ANSWERSnumbers of survivors
If organisms are placed in an environment with unlimited resources, that population of
organisms will probably experience _______. - ANSWERSexponential growth
Individuals in type II populations _______. - ANSWERShave a constant probability of
death throughout their lives
The population size that a particular environment can support is called the _______. -
ANSWERScarrying capacity
The constraint placed on a population by various environmental factors is known as
_______. - ANSWERSenvironmental resistance
Correct Answers
Natural selection acts on individual __________, not on individual genes. -
ANSWERSphenotypes
The total genetic makeup of a population is the _______. - ANSWERSgene pool
One of the assumptions of the Hardy-Weinberg theorem is that _______. -
ANSWERSmating within the population is random
One of the assumptions of the Hardy-Weinberg theorem is that _______. -
ANSWERSmutations must not occur or a mutational equilibrium must exist
The work of Peter and Rosemary Grant, on morphological changes in the bills of
Galápagos finches, shows that evolution can be _______. - ANSWERSrapid
Assuming the conditions set by Hardy-Weinberg equilibrium, if the frequency of
phenotype A is 96%, the frequency of A in the next generation would be _______. -
ANSWERS96%
When the Hardy-Weinberg equilibrium is achieved, evolution _______. -
ANSWERSdoes not occur
Which of the following is not an assumption of the Hardy-Weinberg theorem? -
ANSWERSNatural selection is acting on the population.
When natural selection favors certain phenotypes in a population, the population is
responding to _______. - ANSWERSselection pressure
__________ selection may occur when a phenotype at one extreme of a distribution is
at a disadvantage. - ANSWERSDirectional
When individuals of an intermediate phenotype are at a relative disadvantage within the
population, __________ selection is occurring. - ANSWERSdisruptive
A form of natural selection that occurs when both phenotypic extremes are selected
against is __________ selection. - ANSWERSstabilizing
When chance events influence the frequency of alleles within a population, __________
has occurred. - ANSWERSgenetic drift
, Genetic drift is most likely to have noticeable effects in _______. - ANSWERSsmall,
isolated populations
Overhunting of the elephant seal dramatically reduced its numbers in the 1800s. The
population has since increased, but due to the _____________ effect, its genetic
diversity is still very low. - ANSWERSbottleneck
Mutations of an organism's DNA are _______. - ANSWERSsometimes silent and
carried through generations with no ill effects
In a human population carrying the gene for sickle-cell anemia, and exposed to malaria,
several genotypes persist in a _______. - ANSWERSbalanced polymorphism
The biological definition of a __________ is a group of populations in which genes are
actually, or potentially, exchanged through interbreeding. - ANSWERSspecies
A requirement for speciation is that subpopulations _______. - ANSWERSbecome
reproductively isolated from one another
Geographic isolation can lead to speciation, and when it does, the speciation is called
_______. - ANSWERSallopatric
Parapatric speciation may occur among small, local populations called _______. -
ANSWERSdemes
An animal's __________ includes all of the biotic and abiotic characteristics of the area
in which the animal lives. - ANSWERShabitat
When an abiotic factor is out of the range of tolerance for an animal, it becomes a/an
_______. - ANSWERSlimiting factor
On a survivorship curve, the Y axis records _______. - ANSWERSnumbers of survivors
If organisms are placed in an environment with unlimited resources, that population of
organisms will probably experience _______. - ANSWERSexponential growth
Individuals in type II populations _______. - ANSWERShave a constant probability of
death throughout their lives
The population size that a particular environment can support is called the _______. -
ANSWERScarrying capacity
The constraint placed on a population by various environmental factors is known as
_______. - ANSWERSenvironmental resistance
