Question

When a heterozygous bald man marries a heterozygous non-bald woman, the probability of bald and non-bald sons.
 (A) 3:1
 (B) 1:3
 (C) 1:1
 (D) 2:1

Answer 1

Hint: This can be explained by making a punnett square. It is already given in the question that the traits are heterozygous of male and female. The probability of bald and non-bald sons can be obtained by using Mendel’s laws.

Complete answer: As already given in the question about the traits of the female and male. Both are heterozygous in nature. Man is a heterozygous bald and woman is heterozygous non-bald so first of all, what we have to do is make separate characters by denoting them by alphabets which will represent the dominant and recessive nature.
Male: Heterozygously (Bald): Bb
Female: Heterozygously (Non-bald): Nn
{Capital letter denotes the dominant character and small letters represent the recessive character. Also, Bb is for bald characters and Nn for non-bald}.
Now, we have to cross them by using the punnett square. Putting male characters on one side and female one on the other side. The phenotypic ratio obtained is 3:1, while the genotypic ratio is 1:2:1.
(Phenotype - a set of observable characteristics of an individual resulting from the interaction of its genotype with the environment).
(Genotype - A genotype is an individual’s collection of genes).
Hence, the correct answer is option A.

Note: The genotypic ratio of the hybrid would be 1:2:1. The genotype is expressed when the information encoded in the gene’s DNA is used to make protein and RNA molecules. This term can also refer to the two alleles inherited for a particular gene as it is a collection of genes.