Question 1

Which of the following best describes the function of astrocytes in the central nervous system?

Accepted Answer

They support and brace neurons, regulate the chemical environment, and assist in neurotransmitter recycling.

Question 2

A patient presents with muscle weakness and loss of coordination. MRI reveals multiple scleroses (hardened lesions) in the CNS. Which of the following best explains the physiological basis for these symptoms?

Accepted Answer

Destruction of oligodendrocytes resulting in impaired saltatory conduction in the CNS.

Question 3

Which of the following equations correctly represents Ohm’s law as it applies to neuronal membrane potentials?

Accepted Answer

$$V = I R$$

Question 4

During the generation of an action potential, which event occurs immediately after the membrane potential reaches threshold?

Accepted Answer

Voltage-gated Na+ channels open, causing Na+ influx and rapid depolarization.

Question 5

A local anesthetic is applied to a region of skin. Which of the following best explains why the area becomes numb?

Accepted Answer

The anesthetic blocks voltage-gated sodium channels, preventing action potential propagation.

Question 6

Which of the following is a key difference between graded potentials and action potentials?

Accepted Answer

Graded potentials decay with distance, while action potentials are propagated without decrement.

Question 7

A neuron receives simultaneous excitatory postsynaptic potentials (EPSPs) from multiple presynaptic neurons. This is an example of:

Accepted Answer

Spatial summation

Question 8

Which of the following best describes the role of the sodium-potassium pump in maintaining the resting membrane potential?

Accepted Answer

It pumps three Na+ ions out of the cell and two K+ ions into the cell, maintaining ionic gradients.

Question 9

Which of the following neurotransmitters is most commonly associated with inhibitory postsynaptic potentials (IPSPs) in the central nervous system?

Accepted Answer

Gamma-aminobutyric acid (GABA)

Question 10

A patient is exposed to a neurotoxin that blocks the reuptake of neurotransmitters at the synaptic cleft. What is the most likely effect on synaptic transmission?

Accepted Answer

Neurotransmitter will remain in the synaptic cleft longer, prolonging the postsynaptic response.

Question 11

Which of the following best explains why myelinated axons conduct action potentials more rapidly than unmyelinated axons?

Accepted Answer

Myelin sheaths allow saltatory conduction, where action potentials jump from node to node.

Question 12

Which of the following is true regarding the absolute refractory period of a neuron?

Accepted Answer

No stimulus, regardless of strength, can initiate another action potential.

Question 13

Which of the following best describes the function of microglial cells in the CNS?

Accepted Answer

They act as immune defense cells, phagocytizing debris and pathogens.

Question 14

A neuron in the retina of the eye has one axon and one dendrite. This neuron is classified structurally as:

Accepted Answer

Bipolar

Question 15

Which of the following best describes the effect of opening chemically gated K+ channels on the postsynaptic membrane?

Accepted Answer

It causes hyperpolarization and decreases the likelihood of an action potential.

Question 16

Which of the following is a characteristic of neurotransmitter action at G protein–coupled receptors?

Accepted Answer

It produces slow, prolonged responses by activating second messenger systems.

Question 17

A reflex arc is an example of which type of neural processing?

Accepted Answer

Serial processing

Question 18

Which of the following best describes the role of ependymal cells in the CNS?

Accepted Answer

They line the ventricles and help circulate cerebrospinal fluid.

Question 19

Which of the following is a real-life example of retrograde axonal transport being exploited for medical treatment?

Accepted Answer

Using viruses containing corrected genes to deliver therapy to neurons.

Fundamentals of the Nervous System and Nervous Tissue: Structured Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards