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

It actively transports 3 Na$^{+}$ out and 2 K$^{+}$ in, maintaining ionic gradients.

Question 1

Which of the following best describes the function of oligodendrocytes in the central nervous system?

Accepted Answer

They form myelin sheaths around axons to increase conduction velocity.

Question 2

A patient presents with demyelination in the peripheral nervous system. Which glial cell type is most likely affected?

Accepted Answer

Schwann cells

Question 3

Which of the following is TRUE regarding graded potentials?

Accepted Answer

They can summate to reach threshold and trigger an action potential.

Question 4

What is the major intracellular cation responsible for the resting membrane potential?

Accepted Answer

K$^{+}$

Question 5

Which equation can be used to calculate the equilibrium potential for a specific ion across a membrane?

Accepted Answer

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

Question 6

During an action potential, which phase is characterized by the rapid influx of Na$^{+}$ ions?

Accepted Answer

Depolarization

Question 7

Which of the following best explains why myelination increases the speed of action potential conduction?

Accepted Answer

It allows action potentials to jump between nodes of Ranvier via saltatory conduction.

Question 8

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

Accepted Answer

Summation of graded potentials at the axon hillock

Question 9

Which neurotransmitter is most closely associated with inhibitory postsynaptic potentials (IPSPs) in the central nervous system?

Accepted Answer

GABA

Question 10

Which of the following statements about the refractory period of a neuron is CORRECT?

Accepted Answer

The absolute refractory period ensures action potentials are unidirectional.

Question 11

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

Accepted Answer

Regulating the extracellular environment and maintaining the blood-brain barrier

Question 12

A patient has a mutation that impairs the function of ligand-gated ion channels in neurons. Which process would be most directly affected?

Accepted Answer

Generation of graded potentials at the postsynaptic membrane

Question 13

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$^{+}$ out and 2 K$^{+}$ in, maintaining ionic gradients.

Question 14

Which of the following neurotransmitters is classified as a catecholamine and is derived from the amino acid tyrosine?

Accepted Answer

Dopamine

Question 15

Which process is described by the equation $I = g(V_m - E_{ion})$, where $I$ is the ionic current, $g$ is the conductance, $V_m$ is the membrane potential, and $E_{ion}$ is the equilibrium potential?

Accepted Answer

Determination of the ionic current across a membrane

Question 16

Which of the following best explains the difference between direct and indirect neurotransmitter effects?

Accepted Answer

Direct effects involve neurotransmitters binding to ionotropic receptors, causing immediate ion flow.

Question 17

Which of the following factors would most likely increase the conduction velocity of an action potential along an axon?

Accepted Answer

Increasing the degree of myelination

Question 18

Which of the following best describes the function of microglia in the central nervous system?

Accepted Answer

They act as resident immune cells, removing debris and pathogens.

Question 19

Which of the following is TRUE regarding the all-or-none property of action potentials?

Accepted Answer

Once threshold is reached, an action potential is always generated with the same amplitude.

Question 20

A patient is unable to terminate neurotransmitter action at the synapse efficiently. Which process is most likely impaired?

Accepted Answer

Reuptake of neurotransmitters into the presynaptic neuron

Chapter 11: Nervous System Structure and Function – Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards