In a certain cat, long whiskers (w) are dominant and short whiskers (w) are recessive. two cats have genotypes ww and ww. if they have an offspring with short whiskers, what is the genotype of their offspring?

a. ww
b. ww
c. ww
d. ww

D (ww)

Explanation:

This is a cross involving a single gene coding for whisker length in cats. The allele for long whiskers (W) is dominant over the allele for short whiskers (w) i.e. the W allele will mask the expression of w allele in a heterozygous state.

Since long whisker allele (W) is dominant, it means the dominant trait (long whisker) will be expressed if the genotype if a cat is homozygous dominant (WW) or heterozygous (Ww). However, the recessive trait (short whiskers) can only be phenotypically expressed when the cat's genotype is homozygous recessive (ww).

Therefore, if a cross between a Ww (heterozygous) cat and a ww (homozygous recessive) cat produces an offspring with short whiskers, It means that the offspring has a homozygous recessive genotype (ww) since it expresses the recessive trait.