Suppose that two loci A and B are so closely linked that no

Suppose that two loci A and B are so closely linked that no recombination is possible between them. You cross an AAbb individual with an aaBB individual to produce F1 and the F1 progeny are crossed further to produce F2. What phenotypic ratios and in what proportions do you expect to see in F2?

A) 3 A-B- : 1 aabb
B) 1 A-B- : 1 A-bb : 1 aaB- : 1 aabb
C) 1 A-bb : 2 A-B- : 1 aaB-
D) 9 A-B- : 3 A-bb : 3 aaB- : 1 aabb
E) none of the above ratios will be observe

Solution

Answer.

C) 1 A-bb : 2 A-B- : 1 aaB-

Explanation:

AAbb. X. aaBB------parents

Ab. aB-----gametes

AaBb----------F1

AaBb. X. AaBb. --------F1xF1