Question

(c) based on the data, identify the population that is likely to have the highest frequency of heterozygotes. assuming random mating, calculate the frequency of animals in population 1 that carry both alleles 1 and 3.

(d) a sudden event drastically changes the habitat of each population such that most of the normal vegetation and insects are replaced by other vegetation and insects. one of the scientists claims that population 2 will be the most severely affected. predict the most likely effect of the event on population 2. provide reasoning to justify your prediction.

Explanation:

Part (c)

To determine the population with the highest heterozygote frequency, we use the Hardy - Weinberg principle. For a locus with multiple alleles, the frequency of heterozygotes is maximized when the allele frequencies are more evenly distributed (closer to equal). For calculating the frequency of animals with alleles 1 and 3 in population 1 (assuming random mating), we use the formula for the frequency of a heterozygous genotype \(f = 2p_1p_3\), where \(p_1\) is the frequency of allele 1 and \(p_3\) is the frequency of allele 3.

1. Identify the population with highest heterozygotes:

• Let's assume we have allele frequency data (not shown here, but typically from a table). A population with allele frequencies that are more balanced (e.g., if allele frequencies are \(p_1,p_2,p_3\) and they are closer to each other) will have a higher frequency of heterozygotes. For example, if in population \(X\) the allele frequencies are more evenly distributed compared to others, \(X\) will have the highest heterozygote frequency.

1. Calculate frequency of allele 1 - allele 3 heterozygotes in population 1:

• Suppose from the data, the frequency of allele 1 (\(p_1\)) is \(f_1\) and the frequency of allele 3 (\(p_3\)) is \(f_3\).
• Using the formula for the frequency of a heterozygous genotype for two alleles \(A\) and \(B\) (here alleles 1 and 3), the frequency \(F=2\times p_1\times p_3\).
• For example, if \(p_1 = 0.3\) and \(p_3=0.2\), then \(F = 2\times0.3\times0.2=0.12\).

• Prediction: Population 2 will likely experience a significant reduction in population size (or even face local extinction).
• Reasoning: If population 2 has a relatively low genetic diversity (for example, if it has a narrow range of alleles related to traits like camouflage, food - finding, or resistance to new parasites/predators), and the new habitat has different vegetation and insects, the organisms in population 2 may not be well - adapted to the new food sources, new predators, or new environmental conditions. Organisms with traits that were beneficial in the old habitat may be at a disadvantage in the new habitat. Since they have less genetic variation, there are fewer alleles in the gene pool that could code for traits suitable for the new environment. So, natural selection will act strongly against them, leading to a high mortality rate and a decrease in population size.

Answer:

(The population with the highest heterozygote frequency depends on the allele frequency data. For the calculation part, if we assume \(p_1\) and \(p_3\) are the frequencies of allele 1 and 3 respectively, the frequency of animals with both alleles 1 and 3 is \(2p_1p_3\).)

Part (d)