Answer :
To determine the correct statement about a population's genes, let's analyze each of the given statements:
A. The sum of all the allele frequencies is equal to 100%.
B. The product of all the allele frequencies is equal to 100%.
C. Gene pools account for only a portion of genes.
D. Phenotype frequencies are always stable.
Option A: The sum of all the allele frequencies is equal to 100%.
- In population genetics, allele frequency refers to how common an allele is in a population. The frequencies of all alleles of a gene sum to 100% because this represents the total population. This is a fundamental principle in genetics.
Option B: The product of all the allele frequencies is equal to 100%.
- This statement is incorrect. The product of allele frequencies would not equal 100%. Allele frequencies are proportions that sum up to 1 (or 100%), not multiply to reach 100%.
Option C: Gene pools account for only a portion of genes.
- The gene pool represents all the genes in a given population, not just a portion of them. This statement is inaccurate as it suggests an incomplete representation of genes in the gene pool.
Option D: Phenotype frequencies are always stable.
- Phenotype frequencies can change in a population due to various factors such as natural selection, genetic drift, mutations, and gene flow. Therefore, this statement is not always true.
Given these analyses, the correct answer is:
A. The sum of all the allele frequencies is equal to 100%.
A. The sum of all the allele frequencies is equal to 100%.
B. The product of all the allele frequencies is equal to 100%.
C. Gene pools account for only a portion of genes.
D. Phenotype frequencies are always stable.
Option A: The sum of all the allele frequencies is equal to 100%.
- In population genetics, allele frequency refers to how common an allele is in a population. The frequencies of all alleles of a gene sum to 100% because this represents the total population. This is a fundamental principle in genetics.
Option B: The product of all the allele frequencies is equal to 100%.
- This statement is incorrect. The product of allele frequencies would not equal 100%. Allele frequencies are proportions that sum up to 1 (or 100%), not multiply to reach 100%.
Option C: Gene pools account for only a portion of genes.
- The gene pool represents all the genes in a given population, not just a portion of them. This statement is inaccurate as it suggests an incomplete representation of genes in the gene pool.
Option D: Phenotype frequencies are always stable.
- Phenotype frequencies can change in a population due to various factors such as natural selection, genetic drift, mutations, and gene flow. Therefore, this statement is not always true.
Given these analyses, the correct answer is:
A. The sum of all the allele frequencies is equal to 100%.