Question

In Holsteins, the black and white cattle, solid coat color (S) is dominant over spotted coat color. Give the genotypes of the parent cattle and complete the Punnett Square for each of the following crosses:

a. spotted x spotted
b. homozygous solid x spotted
c. heterozygous solid x spotted
d. heterozygous solid x heterozygous solid

Answer 1

In Holsteins, solid coat color (S) is dominant over spotted coat color. The Punnett Square for each cross can be determined by considering the genotypes of the parent cattle. For each cross, the possible genotypes and proportions of solid and spotted offspring are provided.

Step-by-step explanation:

In Holsteins, solid coat color (S) is dominant over spotted coat color. To determine the genotypes of the parent cattle and complete the Punnett Square for each cross, we need to consider the genotypes of the parent cattle. Let's assume spotted coat color is represented by the lowercase letters (s) and solid coat color is represented by the uppercase letters (S).

a. If both parents are spotted (ss), the Punnett Square would look like:

sS sS

sS sS

Each offspring has a 100% chance of being spotted (ss).

b. If one parent is homozygous solid (SS) and the other parent is spotted (ss), the Punnett Square would look like:

sS ss

SS Ss

Each offspring has a 50% chance of being solid (SS) and a 50% chance of being spotted (Ss).

c. If one parent is heterozygous solid (Ss) and the other parent is spotted (ss), the Punnett Square would look like:

sS ss

Ss Ss

Each offspring has a 50% chance of being solid (Ss) and a 50% chance of being spotted (ss).

d. If both parents are heterozygous solid (Ss), the Punnett Square would look like:

Ss Ss

Ss Ss

Each offspring has a 75% chance of being solid (Ss) and a 25% chance of being spotted (ss).