Download Impulse Conduction Practice Questions

Name: __________________
Date: ________________
Neurons & Impulse Conduction Questions
1. What is the charge or difference in electrical potential for a
“polarized membrane” and how do ion concentrations work to make it
that way? (2 marks)
2. Why does the polarity of a cell membrane reverse during an action
potential? (2 marks)
3. Why do nerve impulses move faster along myelinated neurons? (2
marks)
4. Use the following diagram to answer parts (a) and (b).
Changes in Membrane Potential
+40
Membrane
Potential (mV)
+20
0
-20
B
C
-40
-60
A
Time (ms)
a. Which area of the graph indicates the diffusion of Na+ ions
into the neurons? Explain your answer. (2 marks)
b. Repolarization is occuring in which area? Explain your
answer. (2 marks)
5. Explain the difference between depolarization of a neuron and an
action potential. (2 marks)
6. Some people report they have a high pain tolerance. Explain how
this could be due to threshold levels. (2 marks)
7. Describe the “all-or-none” response. (2 marks)
8. List in a numbered form the events involved in impulse
transmission from the presynaptic neuron to the postsynaptic neuron.
(4 marks)
9. Describe what is meant by “excitatory” and “inhibitory” when
referring to the effects of neurotransmitters on the postsynaptic
membrane. (2 marks)
10. What is the relationship between acetylcholine and
cholinesterase? (1 mark)