Nathanael High

Mrs. Roy

Advanced Biology

12 January 2016

Test for Module #7

1. -Ganglia: groups of neuron bodies found in the PNS

-Spinal Nerves: nerves found in the spine

-Efferent neurons: neurons that transmit action potentials from the CNS to the effector

organs

-Somatic Motor Nervous System: PNS neurons that transmit action potentials from the

CNS to skeletal muscles

-Association neuron: neuron that transmits action potentials from one neuron to another

neuron in the CNS

-Excitability: the ability to undergo an action potential in response to a stimulus

2. A. Presynaptic terminals

B. Node of Ravier (sp?)

C. Golgi apparatus

D. Nucleus

E. Dendrites

F. Cell body

G. Axon hillock

H. Axon

3. It has many, generally three axons.

4. The purpose of a non-ciliated ependymal cell is to secrete cerebrospinal fluid.

5. Autonomic nervous system

6. The three conditions are: a., it must be surrounded by Schwann cells, b., the cell body

must have remained alive, and c., it must be fairly well aligned.

7. Na+ is flooding the axon to make the inside positive, and K+ is only slightly leaking out.

8. This sounds like the repolarization step, when K+ is released outside, and Na+ remains,

so it’s probably back to negative.

9. The potassium-sodium pump will remove three Na+’s for every two K+’s brought in and

restore the axon to a resting balance of -85 mV.

10. A., the action potential might not have been strong enough, resulting in a subthreshold

stimulus, or B., the neuron was in absolute refractory mode, when no action potential will

work on it.

11. This is saltory conduction happening on myelinated axons, and it is MUCH faster.

12. (not exactly sure what this question is looking for) While the volume is low, the potential

difference of each individual action potential would be negative, and after the volume is

boosted, the potential differences would be positive.

13. The frequency of the APs will be less, and much more after he turns the volume up.

14. No

15. The frequency of action potentials will be lower in the postsynaptic neuron than the

presynaptic neuron.

16. This would be an inhibitory synapse, and this is called hyperpolarization.

17. It would probably pass through a Divergent arrangement of neurons.