Neurotransmitters and Their Receptors
Multiple Choice
1. What is the main excitatory neurotransmitter in the adult brain?
a. GABA
b. Glutamate
c. Dopamine
d. Serotonin
e. Norepinephrine
Answer: b
Textbook Reference: Overview
2. To which category of neurotransmitters does acetylcholine belong?
a. Purines
b. Peptides
c. Amino acids
d. Biogenic amines
e. Small-molecule neurotransmitters
Answer: e
Textbook Reference: Acetylcholine
3. What is the mechanism of organophosphate toxicity?
a. Inhibition of acetylcholine reuptake
b. Inhibition of acetylcholinesterase
c. Inhibition of choline reuptake
d. Blockage of postsynaptic channels
e. Interference with the vesicle fusion process
Answer: b
Textbook Reference: Acetylcholine
, 4. Which toxin blocks neuromuscular transmission by irreversibly binding to nicotinic acetylcholine
receptors, thus preventing acetylcholine from opening postsynaptic ion channels?
a. α-bungarotoxin
b. Nicotine
c. Muscarine
d. Atropine
e. Arecoline
Answer: a
Textbook Reference: Acetylcholine
5. Which statement about a nicotinic acetylcholine receptor at the neuromuscular junction
is accurate?
a. It has one binding site, and binding of one molecule of acetylcholine to this site will
activate the receptor.
b. It has three binding sites, and binding of only one molecule of acetylcholine to any of
the sites will activate the receptor.
c. It has two binding sites, and binding of two molecules of acetylcholine, one to each
site, is required to activate the receptor.
d. It has two binding sites, and binding of only one molecule of acetylcholine to either of
the sites will activate the receptor.
e. It has four binding sites, and binding of only three molecules of acetylcholine to any of
the sites is required to activate the receptor.
Answer: c
Textbook Reference: Acetylcholine
6. Which statement about muscarinic acetylcholine receptors is true?
a. They control a ligand-gated channel.
b. They mediate a rapid response to acetylcholine.
c. They are ionotropic receptors.
Multiple Choice
1. What is the main excitatory neurotransmitter in the adult brain?
a. GABA
b. Glutamate
c. Dopamine
d. Serotonin
e. Norepinephrine
Answer: b
Textbook Reference: Overview
2. To which category of neurotransmitters does acetylcholine belong?
a. Purines
b. Peptides
c. Amino acids
d. Biogenic amines
e. Small-molecule neurotransmitters
Answer: e
Textbook Reference: Acetylcholine
3. What is the mechanism of organophosphate toxicity?
a. Inhibition of acetylcholine reuptake
b. Inhibition of acetylcholinesterase
c. Inhibition of choline reuptake
d. Blockage of postsynaptic channels
e. Interference with the vesicle fusion process
Answer: b
Textbook Reference: Acetylcholine
, 4. Which toxin blocks neuromuscular transmission by irreversibly binding to nicotinic acetylcholine
receptors, thus preventing acetylcholine from opening postsynaptic ion channels?
a. α-bungarotoxin
b. Nicotine
c. Muscarine
d. Atropine
e. Arecoline
Answer: a
Textbook Reference: Acetylcholine
5. Which statement about a nicotinic acetylcholine receptor at the neuromuscular junction
is accurate?
a. It has one binding site, and binding of one molecule of acetylcholine to this site will
activate the receptor.
b. It has three binding sites, and binding of only one molecule of acetylcholine to any of
the sites will activate the receptor.
c. It has two binding sites, and binding of two molecules of acetylcholine, one to each
site, is required to activate the receptor.
d. It has two binding sites, and binding of only one molecule of acetylcholine to either of
the sites will activate the receptor.
e. It has four binding sites, and binding of only three molecules of acetylcholine to any of
the sites is required to activate the receptor.
Answer: c
Textbook Reference: Acetylcholine
6. Which statement about muscarinic acetylcholine receptors is true?
a. They control a ligand-gated channel.
b. They mediate a rapid response to acetylcholine.
c. They are ionotropic receptors.
