Question

cats tail length is a trait that is incomplete dominant. when a cat witha short tail length is crossed witha long tail, the offspring all have medium tails. what are the possibilities if you crossed a short tail with a medium tail

Answer 1

Answer:

1/2 medium tail and 1/2 Short tail offsprings

Explanation:

The gene involved here codes for tail length in cats. According to the question, the alleles of the gene (long, L and short, l) exhibits incomplete dominance i.e. one allele is incapable of masking the expression of the other, hence, a heterozygous intermediate (Medium tail) phenotype is formed from both parental combinations.

Based on this analogy, a long-tailed cat will have genotype LL, a short-tailed cat will have genotype ll and a medium-tailed cat will have genotype Ll.

Hence, in a cross between a short tailed cat (ll) and a medium tailed cat (Ll), four possible offsprings will be produced with genotypes: Ll, Ll, ll and ll.

Ll(2) offsprings are medium tailed

ll(2) offsprings are short tailed

Hence, the phenotypic ratio will be 2/4 or 1/2 for medium tail and 2/4 or 1/2 for short tail cats.

Answer 2

Answer:

50% medium tail and 50% short tail.

Explanation:

Let the allele that controls the tail length in cat be represented by T.

Cats with short tail length will have the genotype of tt.

Cats with long tail length will have the genotype of TT.

Since the trait exhibit incomplete dominance, cats with medium tail length will have the genotype of Tt.

A short tail cat (tt) is crossed with a medium tail cat (Tt).

tt   x   Tt = Tt, tt, Tt, and tt

Recall that phenotypically, Tt = medium tail and tt = short tail. Hence, 1/2 or 50% of the offspring will have medium tails while the remaining 1/2 or 50% will have short tails.

Hence, the possibilities are 50% medium and 50% short tail cats.