Question 1

If there are two alleles for a gene in a population, and the frequency of the dominant allele (p)is .5, then the frequency of the recessive allele (q)is ____.

Accepted Answer

The frequency of the recessive allele (q) is calculated as 1 - p, where p is the frequency of the dominant allele. Since p = .5, q = 1 - .5 = .5.

Question 2

Natural selection acts upon the ____ to create microevolutionary change. ​

Accepted Answer

The answer of Natural selection acts upon the ____ to...

Question 3

The contribution an individual makes to the gene pool of the next generation compared to the contributions of other individuals is called ____.

Accepted Answer

Relative fitness refers to how successful an individual is at passing on its genes to the next generation in comparison to other individuals in the same population. It is a measure of how well adapted an individual is to its environment and how successful it is at reproducing. It is an important concept in evolutionary biology as it helps explain how certain traits and genetic variations become more common or rare within a population over time.

Question 4

Microevolution is ____. ​

Accepted Answer

Microevolution refers to changes in the frequency of alleles within a population, such as genetic drift, gene flow, or natural selection. It does not necessarily involve the formation of a new species or the appearance of a new mutation. The gradual change in the form of fossils over time is known as macroevolution. The appearance of a life form adapted to a new adaptive zone may be an outcome of microevolutionary processes but is not synonymous with microevolution.

Question 5

The source of new alleles within a population is ____. ​

Accepted Answer

The source of new alleles within a population is mutation, which is a random process that introduces new genetic variations. Natural selection, nonrandom mating, adaptation, and genetic drift can all act on existing alleles in a population, but they do not generate new alleles by themselves.

Question 6

The phenomenon of chance events causing the allele frequencies in a population to change unpredictably is known as ____. ​

Accepted Answer

The phenomenon of chance events causing the allele frequencies in a population to change unpredictably is known as genetic drift. Gene flow is the movement of alleles between populations through migration, while deleterious mutations are mutations that decrease an individual's fitness. Nonrandom mating refers to individuals choosing their mates based on specific traits, which can also cause changes in allele frequencies, but it is not a phenomenon of chance events. Natural selection is the process by which organisms with advantageous traits are more likely to survive and reproduce, leading to changes in allele frequencies over time.

Question 7

On occasion, a stressful factor such as disease, starvation, or drought kills a large proportion of the individuals in a population, producing ____ that dramatically reduces the population size. ​

Accepted Answer

A population bottleneck occurs when a stressful factor such as disease, starvation, or drought kills a large proportion of the individuals in a population, which dramatically reduces the population size. This can lead to a loss of genetic diversity and can increase the frequency of certain alleles, increasing the likelihood of genetic disorders and reducing the ability of the population to adapt to changing environments.

Question 8

The process by which successful traits become more common in subsequent generations is called ____. ​

Accepted Answer

Natural selection is the process in which traits that enhance survival and reproduction become more common in a population over time. This occurs because individuals with advantageous traits are more likely to survive and pass on their genes to their offspring.

Question 9

Which circumstance violates the conditions of the Hardy-Weinberg model? ​

Accepted Answer

Nonrandom mating violates the Hardy-Weinberg equilibrium, which assumes random mating within the population.

Question 10

The only survivors of a colony on Venus are a man and a woman, who both happen to originally be from southern Ukraine. Their descendants will show the effect of ____.

Accepted Answer

Genetic drift occurs when a small population becomes isolated and their gene pool is reduced through chance events. In this scenario, the two survivors from southern Ukraine represent a very small population, and therefore genetic drift is likely to occur as their descendants inherit a reduced and potentially unique set of genes.

Question 11

If a lethal mutation occurs in a dominant allele, ____ individuals will die from its effects.

Accepted Answer

A lethal mutation in a dominant allele means that even one copy of the mutated allele will result in death. Therefore, both homozygous dominant (which will have two copies of the mutated allele) and heterozygous (which will have one copy of the mutated allele) individuals will die from its effects.

Question 12

The agent of microevolutionary change that is most likely to introduce genetic variation from another population is referred to as ____. ​

Accepted Answer

Gene flow involves the movement of individuals or gametes (reproductive cells) between populations, which introduces new genetic material and potentially increases genetic diversity within a population. This can be an important driver of microevolution because it can bring new alleles (alternative versions of genes) into a population, which can increase the available variation for natural selection to act upon. Genetic drift refers to random fluctuations in allele frequencies due to chance events, while natural selection and nonrandom mating are mechanisms that act on existing genetic variation within a population. Mutation is a source of new genetic variation, but it occurs at a relatively low rate compared to gene flow.

Question 13

Dog breeders produced the long body and short legs of a dachshund by employing ____ selection. ​

Accepted Answer

Directional selection favors extreme variations of a trait, and in this case, breeders selected for the trait of long body and short legs to create the dachshund breed. Dominant selection would not apply as there is no indication of one allele being dominant over another. Stabilizing selection favors the intermediate form of a trait and disruptive selection favors extremes on both ends of the spectrum. Sexual selection would apply if the selection was based on the preferences of the animals themselves rather than human breeders.

Question 14

Directional selection favors ____.

Accepted Answer

Directional selection favors phenotypes at one end of the distribution, leading to a shift in the average phenotype of the population towards that end. This is because individuals with that particular phenotype have a higher fitness and are more likely to survive and reproduce. The opposite end of the distribution will be selected against, leading to a decrease in the frequency of those phenotypes over time.

Question 15

Natural selection that shifts the adaptation of an entire population is known as ____. ​

Accepted Answer

Directional selection is a type of natural selection that shifts the adaptation of an entire population in one direction.

Question 16

Microevolutionary change resulting from the differential survivorship or reproduction of individuals with different genotypes is known as ____.

Accepted Answer

Natural selection is the process by which individuals with advantageous traits are more likely to survive and reproduce, passing those traits on to their offspring. This results in microevolutionary change over time. Nonrandom mating refers to individuals mating based on certain characteristics, while mutation, gene flow, and genetic drift all refer to other sources of genetic variation but do not necessarily result in differential survivorship or reproduction.

Question 17

With ____ selection, the frequency of the mean phenotype decreases while the frequencies of extreme phenotypes increase. ​

Accepted Answer

Disruptive selection favors extreme phenotypes over the mean phenotype, causing the frequency of the mean phenotype to decrease while the frequencies of extreme phenotypes increase.

Question 18

The high incidence of Ellis-van Creveld syndrome among the Old Order Amish population is caused by ____. ​

Accepted Answer

The high incidence of Ellis-van Creveld syndrome among the Old Order Amish population is caused by inbreeding, which is the mating of genetically related individuals. The Amish community is known for practicing endogamy, which means they tend to marry within their own community and gene pool. This increases the chance of inheriting rare genetic disorders, such as Ellis-van Creveld syndrome, in their offspring.

Question 19

In humans, ____ mutations cause forms of Ehlers-Danlos syndrome a disruption of collagen synthesis that may result in loose skin or weak joints. ​

Accepted Answer

Deleterious mutations are harmful to the organism, and in the case of Ehlers-Danlos syndrome, these mutations disrupt collagen synthesis and lead to loose skin or weak joints. Frameshift, advantageous, lethal, and neutral mutations are not specifically implicated in the development of Ehlers-Danlos syndrome.

Question 20

Dispersal agents, such as pollen-carrying wind or seed-carrying animals, are responsible for ____ in most plant populations because they often introduce novel alleles into a population. ​

Accepted Answer

Dispersal agents introduce novel alleles into a population through gene flow, which is the transfer of genes from one population to another. This can increase genetic diversity within a population and reduce the genetic differences between populations.

Quiz 21: Microevolution: Genetic Changes Within Populations

If there are two alleles for a gene in a population, and the frequency of the dominant allele (p) is .5, then the frequency of the recessive allele (q) is ____.

Natural selection acts upon the ____ to create microevolutionary change.

The contribution an individual makes to the gene pool of the next generation compared to the contributions of other individuals is called ____.

Microevolution is ____.

The source of new alleles within a population is ____.

The phenomenon of chance events causing the allele frequencies in a population to change unpredictably is known as ____.

On occasion, a stressful factor such as disease, starvation, or drought kills a large proportion of the individuals in a population, producing ____ that dramatically reduces the population size.

The process by which successful traits become more common in subsequent generations is called ____.

Which circumstance violates the conditions of the Hardy-Weinberg model?

The only survivors of a colony on Venus are a man and a woman, who both happen to originally be from southern Ukraine. Their descendants will show the effect of ____.

If a lethal mutation occurs in a dominant allele, ____ individuals will die from its effects.

The agent of microevolutionary change that is most likely to introduce genetic variation from another population is referred to as ____.

Dog breeders produced the long body and short legs of a dachshund by employing ____ selection.

Directional selection favors ____.

Natural selection that shifts the adaptation of an entire population is known as ____.

Microevolutionary change resulting from the differential survivorship or reproduction of individuals with different genotypes is known as ____.

With ____ selection, the frequency of the mean phenotype decreases while the frequencies of extreme phenotypes increase.

The high incidence of Ellis-van Creveld syndrome among the Old Order Amish population is caused by ____.

In humans, ____ mutations cause forms of Ehlers-Danlos syndrome a disruption of collagen synthesis that may result in loose skin or weak joints.

Dispersal agents, such as pollen-carrying wind or seed-carrying animals, are responsible for ____ in most plant populations because they often introduce novel alleles into a population.

Quiz 21: Microevolution: Genetic Changes Within Populations

If there are two alleles for a gene in a population, and the frequency of the dominant allele (p) is .5, then the frequency of the recessive allele (q) is ____.

Natural selection acts upon the ____ to create microevolutionary change. ​

The contribution an individual makes to the gene pool of the next generation compared to the contributions of other individuals is called ____.

Microevolution is ____. ​

The source of new alleles within a population is ____. ​

The phenomenon of chance events causing the allele frequencies in a population to change unpredictably is known as ____. ​

On occasion, a stressful factor such as disease, starvation, or drought kills a large proportion of the individuals in a population, producing ____ that dramatically reduces the population size. ​

The process by which successful traits become more common in subsequent generations is called ____. ​

Which circumstance violates the conditions of the Hardy-Weinberg model? ​

The only survivors of a colony on Venus are a man and a woman, who both happen to originally be from southern Ukraine. Their descendants will show the effect of ____.

If a lethal mutation occurs in a dominant allele, ____ individuals will die from its effects.

The agent of microevolutionary change that is most likely to introduce genetic variation from another population is referred to as ____. ​

Dog breeders produced the long body and short legs of a dachshund by employing ____ selection. ​

Directional selection favors ____.

Natural selection that shifts the adaptation of an entire population is known as ____. ​

Microevolutionary change resulting from the differential survivorship or reproduction of individuals with different genotypes is known as ____.

With ____ selection, the frequency of the mean phenotype decreases while the frequencies of extreme phenotypes increase. ​

The high incidence of Ellis-van Creveld syndrome among the Old Order Amish population is caused by ____. ​

In humans, ____ mutations cause forms of Ehlers-Danlos syndrome a disruption of collagen synthesis that may result in loose skin or weak joints. ​

Dispersal agents, such as pollen-carrying wind or seed-carrying animals, are responsible for ____ in most plant populations because they often introduce novel alleles into a population. ​

Natural selection acts upon the ____ to create microevolutionary change.

Microevolution is ____.

The source of new alleles within a population is ____.

The phenomenon of chance events causing the allele frequencies in a population to change unpredictably is known as ____.

On occasion, a stressful factor such as disease, starvation, or drought kills a large proportion of the individuals in a population, producing ____ that dramatically reduces the population size.

The process by which successful traits become more common in subsequent generations is called ____.

Which circumstance violates the conditions of the Hardy-Weinberg model?

The agent of microevolutionary change that is most likely to introduce genetic variation from another population is referred to as ____.

Dog breeders produced the long body and short legs of a dachshund by employing ____ selection.

Natural selection that shifts the adaptation of an entire population is known as ____.

With ____ selection, the frequency of the mean phenotype decreases while the frequencies of extreme phenotypes increase.

The high incidence of Ellis-van Creveld syndrome among the Old Order Amish population is caused by ____.

In humans, ____ mutations cause forms of Ehlers-Danlos syndrome a disruption of collagen synthesis that may result in loose skin or weak joints.

Dispersal agents, such as pollen-carrying wind or seed-carrying animals, are responsible for ____ in most plant populations because they often introduce novel alleles into a population.