Question

HELP ASAP PLS!!!! Cystic fibrosis is an inherited genetic disorder that affects the digestive system and the lungs. If a mother carries a recessive allele for a genetic disorder, such as cystic fibrosis, under what circumstances will her children inherit the disorder?
A) The children’s father must also carry the recessive allele.
B) The mother’s father must also carry the recessive allele.
C) The paternal grandfather must also carry the recessive allele.
D) The children must be female like the mother to inherit the disorder.

Answer 1

Answer:

A

Explanation:

For a recessive gene to affect the child they must inherit two recessive alleles because if a dominant allele is inherited than the dominant trait will be the one that is expressed in the child. The only way to get two recessive alleles is to inherit one from both parents so the father must also carry the recessive allele. This means A must be the correct answer.