Bio22 Human Physiology - Nervous System
Homework
1. Graded potentials are short lived and travel only short
distances. Action potentials are long lasting and travel
long distances. Where do graded potentials occur? Where
do action potentials occur? What is the difference in
membrane channels in these two locations and how does
this relate to the differences between graded potentials
and action potentials?
2. If the resting membrane potential of a neuron is -70mV,
give an example of the membrane potential for a
depolarized cell and explain what is happening.
If the resting membrane potential of a neuron is -70mV,
give an example of the membrane potential for a
hyperpolarized cell and explain what is happening.
3. Once AP has begun, second AP can't trigger for about 2
msec, Why?
4. What are the two factors that affect the speed of action
potentials?
5. Describe the difference between continuous conduction
vs saltatory conduction down the length of a neuron and
how this affects the speed of action potentials.
6. What is the cause of multiple sclerosis? What is the
effect of MS? How does MS lead to such a wide range of
symptoms?
7. Describe three ways that neurotransmitters are
terminated. What happens if neurotransmitter
termination is blocked?
8. What effect does an EPSP have on the membrane
potential? What effect does an IPSP have on the
membrane potential? What happens to the membrane
potential when both an EPSP and an IPSP stimulate a
neuron?
