A hormone often has effects only on certain cells. The reason the message of an "inappropriate" hormone is "ignored" by nontarget cells is that the nontarget cells .

A. have receptors for the hormone
B. have enzymes that break down the hormone
C. lack receptors for the hormone
D. lack the genes that the hormone is attempting to activate

Correct option is C

Explanation:

lack receptors for the hormone

what's the question?

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.