Question 1

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

Accepted Answer

It integrates sensory information and coordinates voluntary and involuntary responses.

Question 2

A patient suffers a spinal cord injury that disrupts communication between the brain and the lower limbs. Which division of the nervous system is primarily affected?

Accepted Answer

Central nervous system (CNS)

Question 3

Which of the following is a correct pairing of neuroglial cell and its function?

Accepted Answer

Astrocyte – forms the blood-brain barrier in the CNS

Question 4

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

Accepted Answer

Myelin insulates the axon, allowing action potentials to jump between nodes of Ranvier (saltatory conduction).

Question 5

A local anesthetic such as lidocaine blocks voltage-gated sodium channels. What is the physiological consequence of this action?

Accepted Answer

Neurons cannot depolarize, so action potentials are not generated, resulting in loss of sensation.

Question 6

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

Accepted Answer

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

Question 7

During the depolarization phase of an action potential, which of the following occurs?

Accepted Answer

Voltage-gated sodium channels open and sodium rushes into the cell.

Question 8

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

Accepted Answer

If threshold is reached, an action potential will occur with the same magnitude every time.

Question 9

A neuron receives multiple excitatory postsynaptic potentials (EPSPs) in rapid succession from a single presynaptic neuron. This is an example of:

Accepted Answer

Temporal summation

Question 10

Which of the following events occurs first during chemical synaptic transmission?

Accepted Answer

Action potential arrives at the axon terminal.

Question 11

Which of the following is a characteristic of electrical synapses?

Accepted Answer

They allow bidirectional and nearly instantaneous transmission of signals.

Question 12

Which of the following best describes the role of the sodium-potassium pump in neurons?

Accepted Answer

It maintains the resting membrane potential by actively transporting 3 Na$$^+$$ out and 2 K$$^+ in.$$

Question 13

A patient has a genetic mutation that prevents the formation of Schwann cells. Which of the following would most likely be affected?

Accepted Answer

Myelination of axons in the PNS

Question 14

Which of the following is TRUE regarding the effect of opening ligand-gated chloride channels on the postsynaptic membrane?

Accepted Answer

It causes hyperpolarization and an IPSP.

Question 15

Which of the following is NOT a method for terminating synaptic transmission?

Accepted Answer

Continuous release of neurotransmitter

Question 16

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

Accepted Answer

The refractory period prevents the action potential from traveling backward.

Question 17

A patient is exposed to a toxin that selectively blocks voltage-gated potassium channels. What would be the most immediate effect on the action potential?

Accepted Answer

Repolarization would be delayed, prolonging the action potential.

Question 18

Which of the following neural circuit types allows a single sensory input to affect multiple regions of the brain simultaneously?

Accepted Answer

Diverging circuit

Question 19

Which of the following best describes the effect of an excitatory postsynaptic potential (EPSP)?

Accepted Answer

It moves the postsynaptic membrane potential closer to threshold.

Question 20

Which of the following is the correct sequence of events during an action potential?

Accepted Answer

Depolarization, repolarization, hyperpolarization

Chapter 11: Introduction to the Nervous System and Nervous Tissue - Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards