ATI RN
Test Questions on Autonomic Nervous System MCAT Questions
Question 1 of 5
Parasympathetic fibers arise from which set of cranial nerves?
Correct Answer: C
Rationale: Parasympathetic fibers originate from cranial nerves III (oculomotor), VII (facial), IX (glossopharyngeal), and X (vagus), plus sacral S2-S4. Option C matches this.
Question 2 of 5
The receptors for acetylcholine at the ganglia of both the sympathetic and parasympathetic divisions are:
Correct Answer: C
Rationale: Nicotinic receptors at ANS ganglia (both divisions) bind acetylcholine from preganglionic neurons. Muscarinic are postganglionic, atropine blocks muscarinic, isoproteranol is adrenergic.
Question 3 of 5
A ganglion is an aggregate of nerve cell bodies:
Correct Answer: B
Rationale: Ganglia are clusters of nerve cell bodies outside the CNS (e.g., sympathetic chain). Inside CNS, they’re called nuclei.
Question 4 of 5
Inability to walk a straight line may indicate damage to which cranial nerve?
Correct Answer: A
Rationale: The vestibulocochlear nerve (VIII) mediates balance; damage causes ataxia (e.g., staggering gait). Others affect eye movement or tongue.
Question 5 of 5
Depolarization of the membrane of a nerve cell occurs by the rapid influx of:
Correct Answer: D
Rationale: Depolarization results from sodium (Na⁺) influx through voltage-gated channels during an action potential. Potassium (K⁺) efflux repolarizes, chloride and anions maintain resting state.