A Punnett square for a cross involving 2 genes (each with 2 alleles) has 4 rows and 2 columns.

True or False?

In a Punnett square for a cross is involving 2 genes (each with 2 alleles). In F1 generation, it will bear 2 rows and 2 columns. But in F2 generation the punnett square will have 4 rows and 4 columns (like Mendel's law said). The genotype ratio in F1 generation is 1:2:1 and phenotype ratio is 3:1. so the answer is false.

Explanation:

if 2 genes Aa and Aa {which have 2 alleles (A, a and a, A) } do cross, then it will give,

A a

A AA Aa

a Aa aa

from the above, punnett square it is proved that it will bear 2 rows and 2 columns.