Biology 107

Study Guide: Nervous system I.

Chapter 48

1. What is the difference between the central nervous system and the peripheral nervous system? Which of these systems is most highly specialized for integration? What are sensory input and motor output?
2. What are the cell types of the nervous system? Which are support cells and which are specialized to carry impulses?
3. Be able to identify the following structures on a neuron: dendrite, axon, axon hillock, cell body, nodes, internodes, synaptic terminal. What is the function of each of these structures? Which of these structures receives signals, and which send impulses from the cell body?
4. What are the three major classes of neurons? What is a nucleus and what is a ganglion? Where are they located?
5. What are the types of glia? What is the function of each type of glial cell? Which form myelin?
6. What is the usual voltage across the membrane of a neuron? How does this voltage arise? Where is the highest concentration of sodium and of potassium? What are the principle anions in the cell? How are the large differences in concentrations of sodium and potassium maintained?
7. What is the difference between a graded potential and an action potential?
8. If channels for potassium are opened, will this lead to a hyperpolarization or a depolarization? What is the effect on membrane potential if sodium channels are opened?
9. What are the different phases of an action potential? What part of the neuron can have an action potential? What is the refractory period? What effect does the refractory period have on subsequent action potentials? How does a series of action potentials differ between a weak stimulus and a strong stimulus?
10. How is an action potential able to move along an axon? What factors influence the speed an action potential travels?