Question

In pigs, mule hoof (fused hoof) is dominant (C) while cloven foot is recessive (c). Belted coat pattern (S) is dominant to solid color (s). Give the F2 genotype and phenotype ratios expected from the cross CCSS x ccss.

Answer 1

The F2 genotype ratio from the cross CCSS x ccss in pigs with dominant mule hoof and belted coat pattern would follow a 9:3:3:1 Mendelian ratio, consisting of both dominant traits, one dominant and one recessive trait, and both recessive traits.

Step-by-step explanation:

The question pertains to genetics, specifically to a dihybrid cross involving pigs with certain traits. Mule hoof (fused hoof) is dominant (C) and cloven foot is recessive (c), while belted coat pattern is dominant (S) over a solid color (s). To find out the F2 genotype and phenotype ratios from the cross of two purebred pigs (CCSS and ccss), we must use a Punnett square for dihybrid crosses. This would result in F1 generation all being heterozygous (CcSs), exhibiting the dominant phenotypes. For the F2 generation, the expected genotype ratio from a heterozygous cross (CcSs x CcSs) would follow the 9:3:3:1 Mendelian ratio, which in this case would mean:

Answer 2

The expected genotype and phenotype proportions for F2 would be:

4 CCSS mule hoof individuals with belt pattern.

2 ccSS individuals with split shell with belt pattern.

0 CCss individuals with solid-colored mule hoofs.

2 CCSS individuals with solid color split hull.

To observe F2, we need to understand the genotype of the parents, which are CCSS (mule hoof with belt pattern) and ccss (split hoof with solid color), considering that the first letter represents the gene for the hoof and the second letter for the coat, we would have the following F2 genotypes:

1. CCSs
2. CCSs
3. CCss
4. CCss
5. ccSS
6. ccSS
7. ccSs
8. ccSs

After this, we can observe the patterns of recessivity and dominance between the alleles and we will see the phenotypes mule hoof with belt pattern (CCSS), cloven hoof with belt pattern (ccSS), cloven hoof with solid color (ccss).