Question 1

If all of the alleles of a given locus are the same in a population, then what is the frequency of that allele?

Accepted Answer

If all of the alleles at a given locus in a population are the same, then the frequency of that allele is 1.0, which represents 100% of the alleles.

Question 2

In order to meet the conditions of the Hardy-Weinberg predictions, a population must:

Accepted Answer

In order to meet the conditions of the Hardy-Weinberg predictions, a population must have a very large size, which means that genetic drift (random fluctuations in allele frequencies) will have less impact on the population's gene pool.

Question 3

The Hardy-Weinberg principle is applicable provided that migration:

Accepted Answer

The Hardy-Weinberg principle assumes that there is no migration, as migration can introduce or remove alleles from the population, altering the allele frequencies.

Question 4

If a population of 2000 individuals has 120 aa genotypes, what would the genotype frequency of aa be?

Accepted Answer

Genotype frequency refers to the proportion of a specific genotype within the population. In this case, we are looking for the frequency of the aa genotype. To calculate this, we first need to determine the total number of alleles in the population, which is equal to twice the population size (2 x 2000 = 4000). Of these alleles, 120 are aa homozygotes, meaning that there are 240 copies of the a allele (2 x 120) in the population. 
The frequency of the aa genotype can then be calculated by dividing the number of aa homozygotes by the total population size:

aa genotype frequency = number of aa homozygotes / total population size
aa genotype frequency = 120 / 2000
aa genotype frequency = 0.06

Therefore, the answer is B.

Question 5

What does p ² represent within the Hardy-Weinberg equation?

Accepted Answer

In the Hardy-Weinberg equation, p^2 represents the frequency of the homozygous dominant genotype in the population.

Question 6

In a certain population, the allele frequencies of the M and N blood group alleles are 0.6 and 0.4, respectively. How many of a population of 500 would be expected to have MN blood type if the population is in genetic equilibrium for the MN locus?

Accepted Answer

The frequency of the MN genotype can be calculated using the Hardy-Weinberg equation:
p^2 + 2pq + q^2 = 1
where p is the frequency of the M allele and q is the frequency of the N allele. Since the given allele frequencies are 0.6 and 0.4, respectively, we can substitute these values:
(0.6)^2 + 2(0.6)(0.4) + (0.4)^2 = 0.36 + 0.48 + 0.16 = 1
Therefore, the frequency of the MN genotype is 2pq = 0.48.
To find the number of individuals with the MN genotype in a population of 500, we can multiply the frequency by the total population size:
0.48 x 500 = 240
So, the answer is C.

Question 7

Which is the correct equation for the Hardy-Weinberg principle?

Accepted Answer

The correct equation for the Hardy-Weinberg principle is p^2 + 2pq + q^2 = 1, which is equivalent to choice E in the given options. This equation represents the allele frequencies in a population that is at Hardy-Weinberg equilibrium, where p is the frequency of the dominant allele, q is the frequency of the recessive allele, and pq represents the frequency of heterozygotes. The sum of these frequencies is always equal to 1.

Question 8

In a certain population, the allele causing sickle cell anemia has an allele frequency of 0.2. If the population is in genetic equilibrium for this allele, what fraction of the population would be carriers for the allele (heterozygous individuals)?

Accepted Answer

The frequency of carriers (heterozygous individuals) can be calculated using the Hardy-Weinberg principle, which is 2pq, where p is the frequency of the dominant allele and q is the frequency of the recessive allele. Given q = 0.2, p = 1 - q = 0.8. Therefore, 2pq = 2(0.8)(0.2) = 0.32.

Question 9

Table 19-1  Refer to the accompanying table. What is the frequency of the Dd genotype?

Accepted Answer

The answer of Table 19-1  Refer to the accompanying...

Question 10

What is the study of the genetic variability within a population and the forces that change allele frequencies?

Accepted Answer

The study of the genetic variability within a population and the forces that change allele frequencies is known as population genetics. Population genetics is concerned with understanding how genetic variation arises and is maintained in populations over time through processes such as natural selection, genetic drift, and gene flow. It is a key field within evolutionary biology, as it helps to provide insights into the mechanisms that drive evolutionary change.

Question 11

If an animal population is diploid, then each individual possesses:

Accepted Answer

Diploid means that an individual possesses two sets of chromosomes, one from each parent. Therefore, for each gene locus, an individual would have two alleles, one on each chromosome.

Question 12

If a population of 1000 individuals has 120 aa genotypes, 460 Aa genotypes, and 420 AA genotypes, what is the allele frequency of the dominant allele (A)?

Accepted Answer

The frequency of the dominant allele (A) can be calculated by taking the sum of the homozygous dominant (AA) and half of the heterozygous (Aa) genotypes, then dividing by the total number of alleles. This gives (2*420 + 460) / (2*1000) = 1300 / 2000 = 0.65.

Question 13

If the allele or genotype frequencies deviate from the values predicted by the Hardy-Weinberg principle, the population is:

Accepted Answer

Deviation from Hardy-Weinberg equilibrium indicates that one or more of the conditions for equilibrium are not met, suggesting that evolutionary forces such as natural selection, genetic drift, mutation, migration, or non-random mating are at work, causing the population to evolve.

Question 14

A ____ consists of all of the individuals of the same species that inhabit a particular place at the same time.

Accepted Answer

A population consists of all the individuals of the same species that inhabit a particular place at the same time.

Question 15

Table 19-1
 Refer to the accompanying table. What is the frequency of the dd genotype?

Accepted Answer

The answer of Table 19-1
 Refer to the accompanying table....

Question 16

Table 19-1
 Refer to the accompanying table. What is the allele frequency of d ?

Accepted Answer

The answer of Table 19-1
 Refer to the accompanying table....

Question 17

For the relative proportions of alleles and genotypes in successive generations to stay the same, which condition must be met for the population?

Accepted Answer

If there is no natural selection, then the frequencies of alleles and genotypes will remain the same. If natural selection is occurring, certain alleles may be favored over others and this can change the relative proportions of alleles and genotypes in the population. The other options (B-E) do not necessarily ensure that the relative proportions of alleles and genotypes will stay the same.

Question 18

Why is the Hardy-Weinberg principle useful to biologists?

Accepted Answer

The Hardy-Weinberg principle is useful to biologists because it identifies those factors that can change allele or genotype frequencies. It provides a null hypothesis against which to test for evolutionary forces such as mutation, selection, migration, and genetic drift. By comparing observed frequencies to those expected under the null hypothesis, biologists can infer the relative importance of these forces in shaping genetic variation within and among populations.

Question 19

Under which mating condition is the Hardy-Weinberg principle applicable?

Accepted Answer

The Hardy-Weinberg principle is based on the assumption that mating between individuals in a population is random, meaning that there is no preference for certain genotypes to mate with each other. This assumption allows us to predict the frequencies of alleles and genotypes in the next generation. If mating is nonrandom, the Hardy-Weinberg principle may not be applicable. Therefore, choice B is the best answer.

Question 20

What best describes all of the alleles for all the loci present in a population?

Accepted Answer

The gene pool encompasses all the alleles for all loci in a population, representing the total genetic diversity available.

Quiz 19: Evolutionary Change in Populations

If all of the alleles of a given locus are the same in a population, then what is the frequency of that allele?

In order to meet the conditions of the Hardy-Weinberg predictions, a population must:

The Hardy-Weinberg principle is applicable provided that migration:

If a population of 2000 individuals has 120 aa genotypes, what would the genotype frequency of aa be?

What does p ² represent within the Hardy-Weinberg equation?

In a certain population, the allele frequencies of the M and N blood group alleles are 0.6 and 0.4, respectively. How many of a population of 500 would be expected to have MN blood type if the population is in genetic equilibrium for the MN locus?

Which is the correct equation for the Hardy-Weinberg principle?

In a certain population, the allele causing sickle cell anemia has an allele frequency of 0.2. If the population is in genetic equilibrium for this allele, what fraction of the population would be carriers for the allele (heterozygous individuals) ?

Table 19-1 Refer to the accompanying table. What is the frequency of the Dd genotype?

What is the study of the genetic variability within a population and the forces that change allele frequencies?

If an animal population is diploid, then each individual possesses:

If a population of 1000 individuals has 120 aa genotypes, 460 Aa genotypes, and 420 AA genotypes, what is the allele frequency of the dominant allele (A) ?

If the allele or genotype frequencies deviate from the values predicted by the Hardy-Weinberg principle, the population is:

A ____ consists of all of the individuals of the same species that inhabit a particular place at the same time.

Table 19-1 Refer to the accompanying table. What is the frequency of the dd genotype?

Table 19-1 Refer to the accompanying table. What is the allele frequency of d ?

For the relative proportions of alleles and genotypes in successive generations to stay the same, which condition must be met for the population?

Why is the Hardy-Weinberg principle useful to biologists?

Under which mating condition is the Hardy-Weinberg principle applicable?

What best describes all of the alleles for all the loci present in a population?

Quiz 19: Evolutionary Change in Populations

If all of the alleles of a given locus are the same in a population, then what is the frequency of that allele?

In order to meet the conditions of the Hardy-Weinberg predictions, a population must:

The Hardy-Weinberg principle is applicable provided that migration:

If a population of 2000 individuals has 120 aa genotypes, what would the genotype frequency of aa be?

What does p 2 represent within the Hardy-Weinberg equation?

In a certain population, the allele frequencies of the M and N blood group alleles are 0.6 and 0.4, respectively. How many of a population of 500 would be expected to have MN blood type if the population is in genetic equilibrium for the MN locus?

Which is the correct equation for the Hardy-Weinberg principle?

In a certain population, the allele causing sickle cell anemia has an allele frequency of 0.2. If the population is in genetic equilibrium for this allele, what fraction of the population would be carriers for the allele (heterozygous individuals) ?

Table 19-1 Refer to the accompanying table. What is the frequency of the Dd genotype?

What is the study of the genetic variability within a population and the forces that change allele frequencies?

If an animal population is diploid, then each individual possesses:

If a population of 1000 individuals has 120 aa genotypes, 460 Aa genotypes, and 420 AA genotypes, what is the allele frequency of the dominant allele (A) ?

If the allele or genotype frequencies deviate from the values predicted by the Hardy-Weinberg principle, the population is:

A ____ consists of all of the individuals of the same species that inhabit a particular place at the same time.

Table 19-1 Refer to the accompanying table. What is the frequency of the dd genotype?

Table 19-1 Refer to the accompanying table. What is the allele frequency of d ?

For the relative proportions of alleles and genotypes in successive generations to stay the same, which condition must be met for the population?

Why is the Hardy-Weinberg principle useful to biologists?

Under which mating condition is the Hardy-Weinberg principle applicable?

What best describes all of the alleles for all the loci present in a population?

What does p ² represent within the Hardy-Weinberg equation?