Question

A man having the genotype EEFgGgHH can produce P number of genetically different sperms, and a woman of genotype liLLMmNn can generate Q number of genetically different eggs. Determine the values of P and Q.
A) \[{\text{P = 4, Q = 4}}\]
B) \[{\text{P = 4, Q = 8}}\]
C) \[{\text{P = 8, Q = 4}}\]
D) \[{\text{P = 8, Q = 8}}\]

Answer 1

Hint: Genotype of an individual refers to the sum total of genes inherited from both parents irrespective of whether they are expressed or not. Genotype does not change under the influence of the environment and it is also not influenced by phenotype.

Complete Answer:
The number of types of gametes by an organism\[{\text{ = }}{{\text{2}}^{\text{n}}}\] whether n is the number of heterozygous paves of genes. Here the men with genotype EEFfGgHH is heterozygous for 2 parts of genes (i.e.\[{\text{F/f and G/G}}\]) respectively), so the total numbers of gametes formed by him will be
\[ \to {2^n} = {\text{ }}{2^2} = 4\].
The woman with genotype \[{\text{IiLLMmNn}}\] in heterozygous for \[3\] pairs of genes (i.e.I/i, M/m and Nn I/I) so total number of gametes formed by woman will be
\[ \to {{\text{2}}^{\text{n}}}{\text{ = }}{{\text{2}}^{\text{3}}}{\text{ = 2}} \times {\text{2}} \times {\text{2 = 8}}\]

Hence, man will produce \[4\] sperms and woman will produce \[8\] sperms i.e. \[{\text{P = 4, Q = 8}}\].

Note: Heterozygous means dissimilar alleles for a specific trait. It is to be noted that genotype and phenotype were formulated by Johannsen in 1909 to distinguish the genetic traits from the expressed traits.