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Flashcards in Chapter 19 Deck (26):
1

1. compared with the inside of the cell, the outside of most cell membranes is:
A. Positive
B. Negative
C. Equal
D. None of the above

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2

2. The difference in electrical charge across a plasma membrane is called:
A. Depolarization
B. Membrane potential
C. Both A and B
D. None of the above

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3

3. A neuron's resting membrane potential is:
A. 70mV
B. -70mV
C. 30mV
D. -30mV

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4

4. Which of the following statements is true concerning the sodium-potassium pump?

A. Three sodium ions are pumped out of the neuron for every two potassium ions pumped into the neuron

B. Two sodium ions are pumped out of the neuron for every three potassium ions pumped into the neuron

C. Three sodium ions are pumped out of the neuron for every three chloride ions pumped into the neuron

D. Three sodium ions are pumped out of the neuron for every three potassium ions pumped into the neuron

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5

TRUE OR FALSE
5. ___________ A membrane that exhibits a membrane potential is said to be polarized.

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6

TRUE OR FALSE
6._________ A slight shift away from the resting membrane potential in a specific region of the plasma membrane is often called a stimulus-gated channel

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7

TRUE OR FALSE
7. ________Chlorine ions (Cl-) are the dominant extracellular cations.

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8

8. During a relative refractory period:

A. An action potential is impossible
B. An action potential is possible only in response to a very strong stimuli
C. An action potential is occurring
D. None of the above

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9

9. Voltage-gated channels are:

A. Membrane channels that close during voltage fluctuations
B. Ion channels that ope in response to voltage fluctuations
C. Membrane channels that are altered from an extremely high stimulus
D. None of the above

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10

10. When current leaps across an insulating myelin sheath from node of Ranvier to node of Ranvier, the type of impulse conduction is:
A. Repolarization
B. Refraction
C. Saltatory conductions
D. Diffusion

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11

11. The larger the diameter of a nerve fiber:
A. The sower the speed of conduction
B. The faster the speed of conduction
C. Fiber diameter does not influence speed of conduction
D. The more the speed fluctuates

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12

TRUE OR FALSE
12. _____ action potential and nerve impulse are synonymous

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13

TRUE OR FALSE
13. ______ When repolarization has occurred, an impulse cannot be conducted

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14

TRUE OR FALSE
14. ________ The action potential is an all-or-none response

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15

True or False
15. ________ Many anesthetics function by inhibiting the opening of sodium channels and thus blocking the initiation and conduction of nerve impulses

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16

16. Which of the following structures is not a main component of a chemical synapse?

A. Synaptic knob
B. Synaptic cleft
C. Synaptic process
D. Plasma membrane of postsynaptic neuron

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17

17. A synaptic knob is located on the:

A. Synaptic cleft
B. Axon
C. Dendrite
D. Cell body

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18

18. Which of the following is true of spatial summation?

A. Neurotransmitters released simultaneously from several presynaptic knobs converge on one postsynaptic neuron.
B. Simultaneous stimulation of more than one postsynaptic neuron occurs
C. Impulses are fired in a rapid succession by the same neuron
D. Speed of impulse transmission is increased when several neurotransmitters are released

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19

True or False
19. _____ In an adult, the nervous system is replete with both electrical synapses and chemical synapses

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20

True or False
20. ______ Rapid-succession stimulation of a postsynaptic neuron by a synaptic knob can have a cumulative effect over time that can result in an action potential

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21

True or False
21. ______ Ca++ ions cause the release of neurotransmitters across the synaptic cleft

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22

22. Neurotransmitters are released in a synapse and bind to:
A. Presynaptic terminals
B. The synaptic cleft
C. The base of the axon
D. Receptors on the postsynaptic terminal

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23

23. The main chemical classes of neurotransmitters include all of the following EXCEPT:
A. Acetylcholine
B. Norepinephrine
C. Amino acids
D. Amines

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24

24. Which of the following is NOT an example of an amine neurotransmitter?
A. Serotonin
B. Histamine
C. Glycine
D. Dopamine

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25

25. Severe depression can be caused by a deficit in which of the following neurotransmitters?
A. Acetylcholine
B. Amino acids
C. Amines
D. Neuropeptides

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26

26. Which of the following is NOT a catecholamine?
A. Epinephrine
B. Norepinephrine
C. Dopamine
D. Serotonin

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