ATI RN
Test Questions on Autonomic Nervous System MCAT Questions
Question 1 of 5
The nodes of Ranvier are found on:
Correct Answer: A
Rationale: Nodes of Ranvier are gaps in the myelin sheath on axons, aiding rapid conduction. Axon hillock initiates, terminals release neurotransmitters, and unmyelinated axons lack nodes.
Question 2 of 5
Saltatory conduction in myelinated axons involves:
Correct Answer: B
Rationale: Saltatory conduction is impulse 'jumping' between nodes of Ranvier, speeding transmission. Continuous is unmyelinated, slow isn’t typical, bidirectional is rare.
Question 3 of 5
The undershoot or afterhyperpolarization phase of an action potential is mainly due to:
Correct Answer: B
Rationale: Afterhyperpolarization occurs as K+ continues exiting, overshooting rest potential. Na+ influx stops earlier, Ca2+ is synaptic, Cl- minimal.
Question 4 of 5
In an electrical synapse, direct communication between neurons occurs through structures known as:
Correct Answer: B
Rationale: Gap junctions allow direct ion flow in electrical synapses. Vesicles and neurotransmitters are chemical, myelin insulates.
Question 5 of 5
The paired structures within the lateral ventricles that produce cerebrospinal fluid (CSF) are known as the:
Correct Answer: B
Rationale: Choroid plexuses in ventricles produce CSF. Foramina connect, villi reabsorb, sinuses drain.