Following release from the presynaptic cell, neuropeptides
a. cannot be deactivated by enzymes, whereas small-molecule transmitters diffuse away or are deactivated by reuptake.
b. are deactivated by reuptake, whereas small-molecule transmitters diffuse away or are deactivated by enzymes.
c. can diffuse away from synapses, whereas small-molecule transmitters are deactivated by reuptake.
d. and small-molecule transmitters can be deactivated by diffusion, enzymes, or reuptake.
Question 2
The release of vesicles containing neuropeptides requires
a. higher levels of calcium than the release of small-molecule neurotransmitters.
b. lower levels of calcium than the release of small-molecule neurotransmitters.
c. approximately equal levels of calcium as the release of small-molecule neurotransmitters.
d. no calcium at all.
