Using the principle of independent assortment, complete the Punnett square to show the results of an F1 cross between two individuals heterozygous for both pod color (C = green and c = yellow) and pod shape (S = smooth and s + constricted). The gametes and some of the genotypes of the F2 offspring are given.

9:3:3:1 ( 9 dominant pod color and shape, 3 heterozygous pod color and homozygous recessive pod shape, 3 homozygous recessive pod color and heterozygous pod shape and 1 recessive homozygous pod color and pod shape)

Explanation:

Mendel's law of independent assortment posits that the alleles of two (or more) different genes get assorted into gametes independently of one another. This implies that the allele a gamete receives for one gene does not influence the allele received for another gene.

In the question given;

We will take a critical look at the cross between two pure-breeding pod color and pod shape:

Pod color (green) = C

Pod color (yellow) = c

Pod Shape (smooth) = S

Pod shape (constricted) = s

The F1 progency of the cross between the heterozygous pod color and pod shape will be:

Cc × Ss

= CS, Cs, cS, cs

From the question, we are to complete the punnett square of the results of the F1 generation, i.e if the F1 progeny assorts independently, what will be the results (F2 generation)

i.e : CS, Cs, cS, cs × CS, Cs, cS, cs

The Punnet Square is in the attached file below.

The results of this dihybrid cross are as follows:

CCSS, CCSs, CCSS, CcSs, CCSs, CcSs, CcSS, CcSs, CcSs (all dominant pod color and shape) "9"

CCss, Ccss, Ccss (heterozygous pod color and homozygous recessive pod shape) "3"

ccSS, ccSs, ccSs (homozygous recessive pod color and heterozygous pod shape)

ccss (recessive homozygous pod color and pod shape)

We can therefore conclude that the results of the Punnet Square of the F1 generation is in the ratio of 9:3:3:1