The Purpose of the Myelin That Surrounds the Axon Is

question 100

Multiple Choice

The purpose of the myelin that surrounds the axon is to

• A)keep nerve cells continually active.
• B)help electrical currents cross the synapse completely.
• C)repair neurons within the peripheral nervous system.
• D)protect, insulate, and speed the transmission of an impulse down the axon.

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Definitions:

Dizygotic Twins

Twins that arise from the separate fertilization of two eggs; commonly known as fraternal twins. Compare with monozygotic twins.

Fraternal Twins

Twins that develop from two different eggs fertilized by two different sperm, resulting in siblings that are genetically distinct.

Extraembryonic Membrane

Membranes forming outside the embryo that support its development, including the yolk sac, amnion, chorion, and allantois in vertebrates.

Keeps Embryo Moist

A function of the amniotic egg or other structures in various organisms to prevent desiccation of the embryo in a terrestrial environment.