Neurons- II. Anatomy

Question 1

A. Cell Body

Answer 1

aka perikaryon and soma, contains:

1. nucleus with nucleolus
2. organelles
3. microtubules
4. Nissl bodies (chromatophilic substances- rough ER)
5. neurofibrils

Question 2

Clusters of cell bodies in the C.N.S.

Answer 2

nucleus

Question 3

Clusters of cell bodies in P.N.S.

Answer 3

ganglia

Question 4

B. Dendrites

Answer 4

• “branches”
• processes attached to cell body
• synapse with other neurons
• receptive areas that transmit info. to cell body

Question 5

C. Axon

Answer 5

transmits action potential away from cell body

Question 6

D. Telodendria

Answer 6

“finger-like” projections on both sensory and motor neurons

Question 7

E. Synaptic terminal (synaptic knob)

Answer 7

“finger nails” containing neurotransmitters

Question 8

F. Myelin

Answer 8

1. lipid (white):
   a. insulates (“saltatory conduction”=a.p. jumps from gap to gap along axon)
   b. neurolemmal sheath
2. nodes of Ranvier

Question 9

In P.N.S. myelin is made by

Answer 9

schwann cells

Question 10

In C.N.S. myelin is made by

Answer 10

oligodendrocytes (make myelin that wraps around several axons)