Question

Assuming a typical monohybrid cross in which one allele is completely dominant to the other, what phenotypic ratio is expected if the F1's are crossed?

Answer 1

Answer:

Assuming the dominant allele is represented as A, and the genotype as AA and the recessive as a, and genotype as aa; then the F1 will produce the offispring. Aa, Aa, Aa,Aa in ratio: 1:1:1:1:1

This shows the dominance of allele A.

However if two of  the F1 generation are crossed then:

The  F2 is AA,Aa,Aa,aa the phenotypic ratio is

                        3   ;     1

While the Genotypic ratio is ratio;

  1AA : 2Aa Aa; 1aa(1 ;2;1)

Explanation: