The Temporal Sequence of Puffing in Polytene Chromosomes is Controlled

Question

The temporal sequence of puffing in polytene chromosomes is controlled by
A) ecdysone.
B) testosterone.
C) estrogen.
D) progesterone.
E) insulin.

Accepted Answer

The temporal sequence of puffing in polytene chromosomes is controlled by the hormone ecdysone. This hormone is secreted during the molting stage of insects and triggers the transformation of the larva into a pupa or an adult. Ecdysone regulates the expression of genes involved in cell differentiation, development, and metamorphosis, including those that induce the appearance of puffs in the polytene chromosomes. Therefore, A is the best choice. None of the other hormones mentioned have been directly linked to the regulation of polytene chromosome puffing.