Lecture 1 - Nerve Tissue

Question 1

what are the major divisions of the central nervous system?

Answer 1

brain and spinal cord

Question 2

what are the major divisions of the peripheral nervous system?

Answer 2

cranial nerves and spinal nerves

Question 3

describe the structure of a neuron

Answer 3

cell body
dendrites
axon (myelinated W or unmyelinated G)

Question 4

describe the structure of the dura mater

Answer 4

dense tough sleeve of connective tissue
- epidural space: separates dura from overlying bone, contains blood vessels and fat, anesthetic injected here
- subdural space: separates dura from arachnoid mater, small amount of fluid

Question 5

describe the structure of the arachnoid mater

Answer 5

thin and wispy
- sub arachnoid space: separates arachnoid and pia mater, contains CSF

Question 6

describe the structure of the pia mater

Answer 6

bound tightly to surface of brain and spinal cord

Question 7

describe the circulation and drainage of CSF

Answer 7

secreted from blood vessels in walls of ventricles, circulates around the brain & spinal cord in subarachnoid space, returns to bloodstream by entering vein above brain

Question 8

how is blood supplied to the brain?

Answer 8

4 arteries
right and left internal carotid arteries (branches of common carotid artery enter at base of skull)
right and left vertebral arteries
(branches of the right and left subclavian arteries enter at base of skull)

Question 9

what is the circle of willis?

Answer 9

branches of the internal carotid arteries and vertebral arteries anastomose allowing blood entering these arteries to flow to any part of both cerebral hemispheres

Question 10

what cells create myelin?

Answer 10

Schwann cells

Question 11

what are the major divisions of the ANS?

Answer 11

sympathetic and parasympathetic