12 Questions
What is the analogy used to describe slow transport?
Walking on a busy street
What are the cells called that meet at the region known as a synapse?
Presynaptic cells
What type of diseases are scientists investigating for a potential link to defective axonal transport?
Neurodegenerative diseases
What is the narrow space between two cells at a synapse called?
Synaptic cleft
What is the purpose of the inactivation gate in axonal Na+ channels?
To prevent the escalating depolarization of the cell
What happens when the slower inactivation gate in the Na+ channels finally closes?
Na+ influx stops and the action potential peaks
What is the function of the double-gating mechanism in axonal voltage-gated Na+ channels?
To allow electrical signals to be conducted in only one direction
What is the significance of the refractory period in neurons?
It ensures that once an action potential has begun, a second action potential cannot be triggered for about 1–2 msec
What is the formula for the area of a circle?
A = pi * radius^2
Why are squid, earthworms, and fish mentioned in the context of axon diameter and speed of conduction?
To provide examples of organisms with giant axons used for rapid escape responses
How do complex nervous systems pack more axons into a small nerve?
By using smaller-diameter axons wrapped in insulating membranes of myelin
Why is the conduction of action potentials faster in myelinated axons?
Because myelinated axons have high-resistance membranes to minimize current leak
Explore the concept of axonal transport and its link to inherited and acquired disorders, including microcephaly and other conditions. Learn about recent research findings indicating that slow transport may be due to a 'stop and go' mechanism, similar to driving on a street with many stoplights as an analogy.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
