The Authors Point Out That the Nervous System "House" Would

question 322

Multiple Choice

The authors point out that the nervous system "house" would remain forever dark and lifeless without chemical couriers. Which of the following is NOT one of these messengers?

• A) neurotransmitters
• B) sodium ions
• C) endogenous opioid peptides
• D) endorphins

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Definitions:

All-Or-None

Referring to the fact that a neuron either fires completely or does not fire at all.

Interneurons

Neurons that provide connections between sensory and motor neurons, as well as between themselves, to integrate sensory input and motor output.

Axons

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

Synaptic Knob

The part of a neuron that connects to another neuron or muscle cell, facilitating the transmission of neurotransmitters across the synaptic gap.