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.

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