Textbook Question
During a neurobiology lecture, a professor repeatedly refers to group A and group B fibers, absolute refractory period, and myelin sheath gaps. Define these terms.
556
views
1
rank
11. Nervous Tissue and Nervous System
Propagation of Action Potentials
Multiple Choice
Which of the following best describes the propagation of depolarization down an axon?
A
The action potential travels as a wave of depolarization along the axon membrane.
B
Depolarization occurs only at the axon hillock and does not travel.
C
The action potential is initiated at the axon terminal and moves towards the cell body.
D
Depolarization is a passive process that does not involve ion channels.
Verified step by step guidance1
Understand the concept of an action potential: An action potential is a rapid rise and subsequent fall in voltage or membrane potential across a cellular membrane, primarily in neurons.
Recognize the role of ion channels: Depolarization involves the opening of voltage-gated sodium channels, allowing Na+ ions to enter the neuron, which changes the membrane potential.
Identify the starting point of an action potential: It typically begins at the axon hillock, where the threshold potential is reached, triggering the opening of ion channels.
Describe the propagation of depolarization: Once initiated, the action potential travels as a wave of depolarization along the axon membrane, moving from the axon hillock towards the axon terminal.
Clarify the direction and nature of propagation: The action potential does not move backwards towards the cell body, nor is it a passive process; it actively involves ion channels opening sequentially along the axon.
Related Videos
Related Practice
