Question

Is the answer 25%?
The allele for a widow’s peak has complete dominance over the allele for a straight hairline (w). What is the probability of two parents heterogeneous for a widow’s peak (Ww) having an offspring without a widow’s peak?

Answer 1

Answers:
-0%
-25%
-50%
-75%

Answer 2

"The question tells you that both parents are heterozygous - that is, Ww - for widow's peak. That means that each child has a 25% chance of being homozgyous dominant; a 50% chance of being heterozygous and a 25% chance of being homozygous recessive. That is, 25% + 50% = 75% of offspring will have a widow's peak and 25% won't.
In this case, homozygous recessive corresponds to the phenotype - no widow's peak - which you want the probability of, so the correct answer is 25%."
So 25% is right.
info taken from here :
http://openstudy.com/updates/4f4a625ee4b00c3c5d335a42

Answer 3

Thanks very much :)

Answer 4

yw ;p