Question

Given diagram shows a pair of homologous chromosomes during meiosis.
Maximum crossing over will occur between genes

• A. A and a, D and d
• B. C and d, c and D
• C. B and c, b and C
• D. A and d, a and D

Answer 1

The correct option is D A and d, a and D

An increase in distance between two genes increases the frequency of crossing over, while the closeness of the genes reduces the chances of crossing over. Since (A and d) & (a and D) are located farthest away from each other, maximum crossing over would occur between them.

So the answer is 'A and d, a and D'.