Name: _______________________________________________________ Date: _____________________________ Period: ________
Action Potentials & Synaptic Transmission WS
1. Label structures W, X, Y, and Z.
2. Assume this is a diagram of a resting neuron.
a. Where is potassium (K+) higher, inside or outside
the cell? _______________________________________________
b. Where is sodium (Na+) higher, inside or outside
the cell? _______________________________________________
3. What cell membrane structure is responsible for
stabilizing the resting membrane potential? Explain
(in your own words) how it works.
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4. What process does the graph below depict? ________________________________________________________________
5. Label the graph with the following words/phrases:
hyperpolarization
threshold potential depolarization
repolarization
resting potential
6. What ion is responsible for the depolarization of a neuron? ______________________________________________
7. What ion is responsible for the repolarization of a neuron? ______________________________________________
8. What is another name for an action potential? _____________________________________________________________
9. Match each term to the appropriate description.
A. Action potential B. Depolarization
C. Polarized
F. Refractory period G. Sodium ions
D. Potassium ions E. Repolarization
H. Sodium-potassium pump
______________ 1. Period of repolarization of the neuron during which it cannot respond to a
second stimulus
______________ 2. State in which the resting potential is reversed as sodium ions rush into neuron
______________ 3. Electrical condition of the plasma membrane of a resting neuron
______________ 4. Period during which potassium ions rush out of the neuron
______________ 5. Transmission of the depolarization wave along a neuron’s membrane
______________ 6. The chief positive intracellular ion in a resting neuron
______________ 7. Process by which ATP is used to move sodium ions out of the cell and potassium
ion back into the cell; restores the resting conditions of the neuron
10. Summarize the process of synaptic transmission.
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11. Restate (in plain English) the following phrase:
“Calcium mediates the exocytosis of neurotransmitter.” ___________________________________________________
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12. Explain why the action potential is an all-or-none phenomenon. _______________________________________
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13. Do action potentials occur across the whole plasma membrane simultaneously? Explain your
answer. _______________________________________________________________________________________________________
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