Caffeine Is a Stimulant That Works Because It Acts as A(n)

Multiple Choice

Caffeine is a stimulant that works because it acts as a(n) _______ to the adenosine receptors in a person's brain, and stimulates _______ in that person's heart and liver that increases blood flow and blood glucose.

A) effector; a pathway
B) inhibitor; a cascade pathway
C) inhibitor; a ligand
D) signal; inhibitors
E) pathway; a ligand