Question 1

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

Accepted Answer

It processes incoming sensory data, integrates information, and sends out motor commands.

Question 2

Which type of neuroglial cell is responsible for forming the myelin sheath in the peripheral nervous system (PNS)?

Accepted Answer

Schwann cell

Question 3

A patient is experiencing muscle weakness and tingling in the limbs. An autoimmune attack on which structure is most likely responsible for these symptoms?

Accepted Answer

Myelin sheath of CNS axons

Question 4

Which of the following best explains why action potentials only travel in one direction along an axon?

Accepted Answer

The refractory period prevents the action potential from moving backward.

Question 5

Which of the following is TRUE regarding graded potentials?

Accepted Answer

They are summed at the axon hillock and can be excitatory or inhibitory.

Question 6

What is the main function of astrocytes in the central nervous system?

Accepted Answer

Anchoring neurons and blood vessels, and regulating extracellular ion concentrations

Question 7

Which of the following best describes the difference between a neuron and a nerve?

Accepted Answer

A neuron is a single excitable cell, while a nerve is a bundle of many neurons.

Question 8

Which of the following equations correctly represents the resting membrane potential of a neuron?

Accepted Answer

$$V_{rest} = -70\ \mathrm{mV}$$

Question 9

A ligand-gated sodium channel opens in response to acetylcholine. What is the most likely effect on the postsynaptic neuron?

Accepted Answer

The membrane potential becomes less negative (depolarized).

Question 10

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

Accepted Answer

Myelin allows action potentials to jump between nodes of Ranvier, a process called saltatory conduction.

Question 11

Which of the following is a function of microglia in the CNS?

Accepted Answer

Acting as immune defense by removing damaged neurons and debris

Question 12

A neuron receives both excitatory and inhibitory inputs. What determines whether it will fire an action potential?

Accepted Answer

The sum of all graded potentials at the axon hillock reaching threshold ($$-55\ \mathrm{mV})$$

Question 13

Which of the following best describes the role of the Na+/K+ ATPase in maintaining the resting membrane potential?

Accepted Answer

It actively transports 3 Na+ out and 2 K+ into the cell, using ATP.

Question 14

A local anesthetic like lidocaine prevents the opening of voltage-gated Na+ channels. What is the physiological consequence of this action?

Accepted Answer

Nerve impulses cannot be conducted, so pain signals do not reach the brain.

Question 15

Which of the following is a correct pairing of neuron structure and function?

Accepted Answer

Bipolar neuron – found in the retina and olfactory system

Question 16

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

Accepted Answer

They produce and circulate cerebrospinal fluid.

Question 17

A patient is given a drug that blocks the reuptake of serotonin in the brain. What is the expected effect on neurotransmission?

Accepted Answer

Serotonin remains in the synaptic cleft longer, enhancing its effect.

Question 18

Which of the following best explains why damage to the CNS is less likely to be repaired than damage to the PNS?

Accepted Answer

Neuroglial cells in the CNS do not support regeneration as Schwann cells do in the PNS.

Question 19

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

Accepted Answer

If threshold is reached, an action potential occurs fully; if not, it does not occur at all.

Nervous Tissue: Structure, Function, and Electrophysiology

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드