Question 1

Which of the following best describes the role of astrocytes in the central nervous system (CNS)?

Accepted Answer

They support neurons by regulating the extracellular environment and maintaining the blood-brain barrier.

Question 2

A patient suffers a spinal cord injury that disrupts the transmission of motor output but leaves sensory input intact. Which part of the nervous system is most likely damaged?

Accepted Answer

Motor (efferent) division of the PNS

Question 3

Which of the following is TRUE regarding the propagation of action potentials in myelinated axons?

Accepted Answer

Action potentials jump from one node of Ranvier to the next, a process called saltatory conduction.

Question 4

Which equation best represents the Nernst equation for calculating the equilibrium potential for potassium ($$K^+) $$ions across a neuronal membrane?

Accepted Answer

$$E_{K^+} = \frac{RT}{zF} \ln \frac{[K^+]_{out}}{[K^+]_{in}}$$

Question 5

Which of the following best explains why neurons have a high metabolic rate?

Accepted Answer

They must maintain ionic gradients across their membranes, which requires continuous ATP consumption.

Question 6

A drug that blocks voltage-gated sodium channels would have what effect on neuronal signaling?

Accepted Answer

It would prevent the initiation and propagation of action potentials.

Question 7

Which of the following is a correct pairing of a neurotransmitter and its typical effect?

Accepted Answer

Acetylcholine – excitatory at neuromuscular junctions in skeletal muscle

Question 8

Which of the following best describes the difference between graded potentials and action potentials?

Accepted Answer

Graded potentials decay with distance, while action potentials do not.

Question 9

A patient is exposed to a toxin that selectively destroys oligodendrocytes. Which of the following would most likely result?

Accepted Answer

Loss of myelin in the central nervous system, leading to impaired neural transmission

Question 10

Which of the following scenarios best illustrates the function of microglial cells?

Accepted Answer

A neuron is damaged by trauma, and nearby cells migrate to engulf the debris.

Question 11

Which of the following is TRUE regarding the absolute refractory period during an action potential?

Accepted Answer

Voltage-gated sodium channels are inactivated, preventing another action potential.

Question 12

Which of the following best describes the effect of myelination on axonal conduction velocity?

Accepted Answer

Myelination increases conduction velocity by allowing action potentials to jump between nodes of Ranvier.

Question 13

Which of the following is a correct statement about the functional classification of neurons?

Accepted Answer

Sensory (afferent) neurons transmit impulses from sensory receptors toward the CNS.

Question 14

Which of the following best explains why graded potentials are important for initiating action potentials?

Accepted Answer

They can summate to depolarize the membrane to threshold at the axon hillock.

Question 15

Which of the following neurotransmitters is degraded by acetylcholinesterase in the synaptic cleft?

Accepted Answer

Acetylcholine

Question 16

A neuron receives both excitatory and inhibitory postsynaptic potentials (EPSPs and IPSPs) at the same time. What determines whether an action potential will be generated?

Accepted Answer

The sum of all EPSPs and IPSPs at the axon hillock reaching threshold

Question 17

Which of the following best describes the function of Schwann cells?

Accepted Answer

They form myelin sheaths around axons in the PNS.

Question 18

Which of the following is a characteristic of multipolar neurons?

Accepted Answer

They are the most common neuron type in the CNS.

Question 19

Which of the following best describes the 'all-or-none' phenomenon of action potentials?

Accepted Answer

If threshold is reached, an action potential will fire completely; if not, it will not fire at all.

Question 20

Which of the following neurotransmitters is a peptide that acts as a natural opiate to reduce pain perception?

Accepted Answer

Endorphins

Fundamentals of the Nervous System and Nervous Tissue: Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards