Question

If an individual that is homozygous

dominant for a specific gene mates with
an individual that is heterozygous for that
gene, the frequency of heterozygotes
among the offspring will be:

A. 0%
B. 25%
C. 33%
D. 50%
E. 75%
F. 100%

Answer 1

In a mating between a homozygous dominant individual and a heterozygous individual, the frequency of heterozygous offspring will be 50%, as the homozygous dominant parent can only pass on the dominant allele, resulting in half of the offspring being heterozygous.

Step-by-step explanation:

If an individual that is homozygous dominant for a specific gene mates with an individual that is heterozygous for that gene, the frequency of heterozygotes among the offspring will be 50%. This can be explained using simple Mendelian genetics. The homozygous dominant individual (AA) can only pass on the dominant allele (A), while the heterozygous individual (Aa) can pass on either the dominant allele (A) or the recessive allele (a). When we combine these possibilities, we get the following genotypes for the offspring: AA and Aa. Since the dominant individual can only pass on the A allele, half of the offspring will be Aa, inheriting the A from the dominant parent and the a from the heterozygous parent.

In this mating scenario, we do not get any offspring with aa genotype because one parent is homozygous dominant. Therefore, the correct answer to the frequency of heterozygotes among the offspring is D. 50%.