Questions for Neuroscience II

1. Describe the electrical events during an action potential.

2. Describe the behavior of Na⁺ K⁺ and Ca⁺⁺ channels as an action potential travels down an axon and reached the axon terminal.

3. Describe the role of Na⁺ K⁺ and Ca⁺⁺ pumps in maintaining the membrane potential. Include the directions the pumps send their ions. Indicate if ATP is required.

4. Show an action potential, label each part and show how small stimuli do cause and action potential but as the stimulus increases, a point is reached in which the V_m increases sharply.

5. Show an action potential. Below the graph, show the change in conductance of Na⁺ and K⁺. How can you explain the relationships between changes in V_m and conductance changes?

6. Write out the Nernst Equation. Indicate when the follow change, what happens to the V_m when these single events happen while all else remains constant:
P_k increases
P_na decreases
Temperature increases
(be careful about the sign of the V_m)

7. Explain the absolute and relative refractory periods. Explain why it is this way in neurons.

8. How does a voltage clamp study work? What does the current flow look like when just K⁺ or just Na⁺ channels are opened?

9. Describe salutatory conduction down an axon. Indicate how invertebrates increase the speed of conduction down the axon.

10. Name major neurotransmitters. When you can, indicate their major precursor that can be used to drive up the neurotransmitter synthesis.

11. Show examples of converging, diverging and reverberating circuits. Indicate an animal behavior that may use each of these circuits to express itself, at least in a short period of time.