Question

A human male produces diallelic sperms in an equal proportion such as AB, Ab, aB and ab. The genotype of the person should be __________.

• A. AaBb
• B. AaBB
• C. AABb
• D. AABB

Answer 1

Answer: (A)

AaBb

Being a product of meiosis, a gamete carries half the number of genes than the somatic cell of an individual. Here, sperms are diallelic which means that the person carries four genes. The total possible type of gametes produced by an organism is 2${}^n$, where n is the number of genes for which the person is heterozygous. Here, the person forms four different types of gametes which mean that he is heterozygous for two genes; 2${}^2$=4. Genotype AaBb is heterozygous for two genes. Genotype AaBB is heterozygous for one gene and thus can make two types of gametes (AB and aB). Genotype AABb is heterozygous for one gene and thus can make two types of gametes (AB and Ab. Genotype AABB is homozygous for both genes and thus can make one type of gametes (AB). Thus, the correct answer is option A.