Question 1

Which of the following best describes the anatomical divisions of the nervous system?

Accepted Answer

The central nervous system includes the brain and spinal cord, while the peripheral nervous system includes cranial and spinal nerves.

Question 2

A patient is unable to contract their skeletal muscles voluntarily but has normal function of smooth and cardiac muscle. Which division of the nervous system is most likely affected?

Accepted Answer

Somatic nervous system

Question 3

Which type of neuroglia is responsible for forming the myelin sheath in the central nervous system (CNS)?

Accepted Answer

Oligodendrocytes

Question 4

Which of the following best describes the resting membrane potential of a typical neuron?

Accepted Answer

The inside of the neuron is negative relative to the outside, with an average resting potential of $$-70\ \mathrm{mV}.$$

Question 5

Which of the following events occurs first during the generation of an action potential?

Accepted Answer

Depolarization to threshold at the axon hillock

Question 6

A neuron receives two subthreshold excitatory stimuli from the same presynaptic neuron in rapid succession, resulting in an action potential. This is an example of:

Accepted Answer

Temporal summation

Question 7

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

Accepted Answer

Saltatory propagation allows action potentials to jump between nodes of Ranvier.

Question 8

Which of the following is a function of astrocytes in the central nervous system?

Accepted Answer

Maintaining the blood-brain barrier

Question 9

A patient with multiple sclerosis experiences muscle weakness and loss of coordination. Which of the following best explains the underlying cause?

Accepted Answer

Destruction of myelin sheaths in the CNS slows or blocks action potential conduction.

Question 10

Which of the following neurotransmitters is primarily inhibitory in the brain and is associated with reducing neuronal excitability?

Accepted Answer

GABA (Gamma aminobutyric acid)

Question 11

During the absolute refractory period, which of the following is true?

Accepted Answer

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

Question 12

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

Accepted Answer

It actively transports 3 Na$$^+$$ ions out of the cell and 2 K$$^+$$ ions into the cell, maintaining the negative resting potential.

Question 13

Which of the following is true regarding graded potentials?

Accepted Answer

They are decremental, meaning their effect decreases with distance from the site of stimulation.

Question 14

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

Accepted Answer

White matter consists mainly of myelinated axons, while gray matter contains neuron cell bodies and unmyelinated fibers.

Question 15

A neuron has three or more processes extending from its cell body. According to structural classification, this neuron is:

Accepted Answer

Multipolar

Question 16

Which of the following best describes the sequence of events at a cholinergic synapse?

Accepted Answer

Action potential arrives at axon terminal, voltage-gated Ca$$^{2+}$$ channels open, acetylcholine is released, diffuses across synaptic cleft, and binds to receptors on the postsynaptic neuron.

Question 17

Which of the following would most likely result in an inhibitory postsynaptic potential (IPSP)?

Accepted Answer

Opening of chemically-gated K$$^+$$ channels, causing K$$^+ to $$leave the cell

Question 18

Which axon type conducts action potentials the fastest?

Accepted Answer

Type A fibers

Question 19

A patient is diagnosed with Parkinson’s disease. Which neurotransmitter is most directly involved in the pathophysiology of this disorder?

Accepted Answer

Dopamine

Question 20

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

Accepted Answer

Any stimulus that reaches threshold will produce an action potential of the same magnitude.

Chapter 12 Notes

Study Guide - Practice Questions

Study Guide - Flashcards