Question 1

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

Accepted Answer

They support and brace neurons, anchor them to nutrient supplies, and help control the chemical environment.

Question 2

A patient is diagnosed with multiple sclerosis, a disease that damages the myelin sheath in the CNS. Which type of neuroglial cell is primarily affected?

Accepted Answer

Oligodendrocytes

Question 3

Which of the following statements about the resting membrane potential ($$V_r) of a $$neuron is correct?

Accepted Answer

It is maintained by differential permeability to $$Na^+$$ and $$K^+$$ and the operation of the sodium-potassium pump.

Question 4

Which of the following best explains why action potentials are described as 'all-or-none' events?

Accepted Answer

Once threshold is reached, the action potential always occurs with the same magnitude, regardless of stimulus strength.

Question 5

A neuron receives a stimulus that causes the inside of its membrane to become less negative. Which event is occurring?

Accepted Answer

Depolarization

Question 6

Which of the following correctly matches the neuroglial cell with its function in the peripheral nervous system (PNS)?

Accepted Answer

Schwann cells – form myelin sheath around axons in the PNS

Question 7

A researcher is studying the flow of ions across a neuron's membrane. Which equation best represents the electrochemical gradient that drives ion movement?

Accepted Answer

$$E_{ion} = \frac{RT}{zF} \ln \left( \frac{[ion]_{out}}{[ion]_{in}} \right)$$

Question 8

Which of the following is a correct structural classification of neurons based on the number of processes extending from the cell body?

Accepted Answer

Unipolar neurons have a single, short process that splits into peripheral and central processes.

Question 9

During an action potential, which sequence of ion channel events occurs?

Accepted Answer

Voltage-gated $$Na^+$$ channels open, causing depolarization, then voltage-gated $$K^+$$ channels open, causing repolarization.

Question 10

A patient has a genetic defect that prevents the formation of Nodes of Ranvier. Which of the following would most likely be affected?

Accepted Answer

The speed of saltatory conduction along myelinated axons

Question 11

Which of the following best describes the difference between gray matter and white matter in the CNS?

Accepted Answer

Gray matter consists mostly of neuron cell bodies and unmyelinated fibers, while white matter is composed of myelinated fibers.

Question 12

Which of the following is a functional classification of neurons that carry impulses away from the central nervous system?

Accepted Answer

Motor (efferent) neurons

Question 13

A neurotransmitter binds to a receptor on the postsynaptic membrane, causing a chemically gated ion channel to open. Which of the following best describes this process?

Accepted Answer

The channel opens when a specific chemical (neurotransmitter) binds to the receptor.

Question 14

Which of the following best explains why neurons are considered 'amitotic'?

Accepted Answer

They lack centrioles and do not undergo mitosis after differentiation.

Question 15

Which of the following events occurs during the absolute refractory period of an action potential?

Accepted Answer

No action potential can be generated, regardless of stimulus strength.

Question 16

A neuron is exposed to a toxin that blocks the sodium-potassium pump. What is the most likely effect on the neuron's resting membrane potential ($$V_r$$)?

Accepted Answer

The resting membrane potential will be lost, approaching zero.

Question 17

Which of the following best describes the direction of information flow in a typical reflex arc involving sensory and motor neurons?

Accepted Answer

Sensory neuron → interneuron → motor neuron

Question 18

Which of the following is NOT a function of neuroglia (glial cells)?

Accepted Answer

Transmitting electrical signals over long distances

Question 19

A patient has a loss of cerebrospinal fluid (CSF) circulation in the brain. Which neuroglial cell type is most likely malfunctioning?

Accepted Answer

Ependymal cells

Question 20

Which of the following best describes the process of saltatory conduction in myelinated axons?

Accepted Answer

Action potentials jump from one Node of Ranvier to the next, increasing conduction speed.

Fundamentals of the Nervous System and Nervous Tissue (Chapter 11) – Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards