After an impulse, the __________ refractory period is the time when it is possible to initiate another impulse, but it requires a stronger than usual stimulus.
Indicate whether this statement is true or false.
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Question 2) Somatic motor neuron axons fall into the category of
A. A fibers.
B. B fibers.
C. C fibers.
D. D fibers.
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Question 3) Arrival of an action potential at the synaptic knob results in
A. opening of voltage-gated calcium channels and diffusion of calcium into the synaptic knob.
B. opening of voltage-gated calcium channels and diffusion of calcium out of the synaptic knob to the interstitial fluid.
C. closure of voltage-gated calcium channels in the synaptic knob membrane.
D. opening of chemically gated calcium channels and diffusion of calcium into the synaptic knob.
E. opening of chemically gated calcium channels and diffusion of calcium out of the synaptic knob to the interstitial fluid.
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Question 4) The process by which the notochord induces the formation of the neural tube is known as _________.
Fill in the blank with correct word.
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Question 5) Saltatory conduction occurs in
A. myelinated axons, where action potentials occur only at neurofibril nodes.
B. myelinated axons, where action potentials occur only under the myelin sheath.
C. myelinated axons, where action potentials occur continuously down the entire axon.
D. unmyelinated axons, where action potentials occur continuously down the entire axon.
E. the axon terminal, where full-size action potentials occur at the hillock.
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Question 6) Substance P is a neuropeptide that functions in the transmission of pain information to the brain.
Indicate whether this statement is true or false.
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Question 7) Imagine a genetic mutation that resulted in a malfunctioning inactivation gate in a voltage-gated sodium channel. The defective gate wouldn't always open and close when it should. What functional problems would this cause for the neurons?
What will be an ideal response?
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Question 8) Voltage-gated sodium channels at a neuron's initial segment are triggered to open when the membrane becomes more positive.
Indicate whether this statement is true or false.
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Question 9) The hyperpolarization that occurs at the end of an action potential is due to the prolonged
A. open state of voltage-gated sodium channels.
B. closure of chemically gated sodium channels.
C. open state of voltage-gated potassium channels.
D. closure of voltage-gated potassium channels.
E. open state of chemically gated sodium channels.
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Question 10) Which occurs first?
A. Absolute refractory period
B. Relative refractory period
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