Question

n humans, freckles (F) on the skin are dominant to no freckles (f). If two parents are heterozygous for the trait, which statement below best describes their chances of having a child with no freckles?
A
If the parents already have three children with freckles, then they are more likely to have a child without freckles.
B
Every time they reproduce, the parents have a one in four chance of having a child without freckles.
C
It would be extremely rare for the freckled parents to have a child without freckles because freckles are dominant.
D
The parents will have three children with freckles before they have a child without freckles.

Answer 1

B

Two Ff parents produce offspring with genotypes FF, Ff, ff in a 1:2:1 ratio, so each child has a 1/4 chance of being ff (no freckles). Each pregnancy is an independent event.