L34. Nervous System Overview

Question 1

Name the 2 types of nervous system cells.

Answer 1

Neurons (nerve cells)

Glia (glial cells)

Question 2

Give a comparison between glia and neurons.

Answer 2

Glia are more numerous than neurons.

Question 3

What do glia do?

Answer 3

Form myelin

Question 4

What do Schwann calls and oligodendrocytes do?

Answer 4

Schwann cells myelinate axons in the peripheral nervous system.
Oligodendrocytes myelinate axons in the CNS.

Question 5

What are astrocytes involved in?

Answer 5

CNS neuron nutrient supply.

Question 6

What are microglia involved in?

Answer 6

Defence role, phagocytic.

Question 7

What are ependymal cells involved in?

Answer 7

production of cerebrospinal fluid.

Question 8

What components make up the PNS?

Answer 8

Spinal nerves, cranial nerves.

Question 9

Name the pairs of spinal nerves.

Answer 9

31 pairs :
8 cervical
12 thoracic
5 lumbar
5 sacral
1 coccygeal

Question 10

What is a myotome?

Answer 10

The group of muscle a spinal nerve innervates (motor)

Question 11

What is a dermatome?

Answer 11

The area of skin a nerve innervates (sensory)

Question 12

Describe 2 types of peripheral nerves and what they do.

Answer 12

Afferent (sensory) - carries info to CNS

Efferent (motor) - carries info away from CNS. Causes muscle contractions.

Question 13

What is the difference between somatic and visceral efferents?

Answer 13

Somatic efferents - voluntary muscle

Visceral efferents - autonomic nervous system.

Question 14

Name the 5 layers from outermost to innermost of a peripheral nerve.

Answer 14

Epineurium
Perineurium
Endoneurium
Schwann cell
Axon