Question

Red-green color blindness is caused by an X-linked recessive gene. In a family, the mother is a carrier of this gene while the father does not have the gene. What are the possible effects on their children?
A.Half of the daughters are normal and half of the daughters are color-blind.
B.Half of the boys are normal and half of the boys are color-blind.
C.Half of the boys are color-blind and half of the girls are color-blind.

Answer 1

What do u think the answer is ?:)

Answer 2

c or b . wby

Answer 3

What are the answers again ?

Answer 4

A.Half of the daughters are normal and half of the daughters are color-blind.
B.Half of the boys are normal and half of the boys are color-blind.
C.Half of the boys are color-blind and half of the girls are color-blind.

Answer 5

because it is an X-linked recessive gene,the genotype of the afflicted person should be XcXc or XcY,
where Xc represents the carrier.
in the case given in the question,genotype of mother is XcX(since mother is a carrier and not afflicted therefore it is heterozygous)and that of father is XY.
possibilty of genotypes of progeny will be-
for daughters :
1.XcX
2.XX

for sons :
1.XcY
2.XY

this means no daughter will be color-blind and half of the sons will be color-blind.

so the answer is B