Multiple Choice
Identify the
letter of the choice that best completes the statement or answers the question.
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1.
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When
an impulse moves down the axon, a. | sodium ions first rush out of the
cell. | b. | a small part of the axon momentarily reverses its
polarity. | c. | the resting potential of the cell does not
change. | d. | potassium ions are pumped into the
axon. | | |
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2.
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When
a neurotransmitter is released from a presynaptic neuron, the neurotransmitter may a. | become an enzyme
in the space between the neurons. | b. | bind to membrane receptor proteins on the membrane of the
postsynaptic neuron. | c. | cover the membrane of the axon. | d. | cause the cell
body of the postsynaptic neuron to enlarge. | | |
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3.
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Refer
to the illustration above. If neurotransmitters could not be cleared out of a synapse after
transmitting a message, a. | a postsynaptic neuron would continue to be stimulated for an
indefinite period of time. | b. | the presynaptic neuron could not pass on its
impulse. | c. | the postsynaptic neuron would not be
stimulated. | d. | None of the above | | |
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4.
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The
central nervous system consists of a. | the brain and spinal cord. | c. | the spinal cord only. | b. | spinal nerves
only. | d. | the brain
only. | | | | |
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5.
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Sensory receptors essential for balance are located in the a. | eyes. | c. | cochlea of the
inner ear. | b. | eardrum. | d. | semicircular canals. | | | | |
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