Cystic fibrosis (cf) is caused by a recessive allele. a couple who do not have cf have a child that has cf. what is the probability that if they have another child, that the child will be heterozygous for cf?

50% but some times that child be comes a carrier. it is hard to explain even for me. i have it and i only know a little, so to help you out, here is an image.

hope this helps

the correct answer is - ability to find a mate

stress fractures occur largely in the feet and legs and are common in sports that require repetitive impact, primarily running/jumping sports such as gymnastics or track and field.