Question

Birds’ testes/ovaries enlarge during the breeding season and then shrink back down to a 10th of their previous size prior to migration?

a.True

b. False

Answer 1

Answer: True.
Explanation:
In birds, the size of reproductive structures varies depending upon the time of breeding/non-breeding season. Bird's reproductive organs (Ovaries/testis) increase in size during reproductive/breeding season and shrink back to their normal size during the non-breeding season.

The shrinkage of reproductive structures during migration/non-breeding season streamlines their body for more adapted flight. It also reduces sex drive in birds and conserves energy for flying and staying warm.