The Mass Number of an Isotope Is the Sum of the Number

question 93

True/False

The mass number of an isotope is the sum of the number of protons and neutrons in its nucleus.

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Definitions:

Axons

Long threadlike part of a nerve cell along which impulses are conducted from the cell body to other cells.

Myelinated axons

Nerve fibers covered in myelin, a protective sheath that speeds up the transmission of electrical signals in the nervous system.

White matter

Tissue in the brain and spinal cord made up primarily of nerve fibers and is responsible for communication between different brain regions and between the brain and the spinal cord.

Neurotransmitter

A chemical within the vesicles of the synaptic knob that is released into the postsynaptic structures when a nerve impulse reaches the synaptic knob.