DLA 27 +DLA 28

Question 1

What is the BBB?

Answer 1

Protects the CNS from imbalances in surrounding
environment- electrolytes, hormones, metabolites

complex tight junction, continuous basal lamina

surrounded by foot processes of astrocytes

can lose effectiveness during certain diseases

some parts have no barrier (homeostatic reasons)

Question 2

What is multiple sclerosis?

Answer 2

autoimmune disorder that targets myelins basic protein

CNS

Question 3

What are the three stages of the demyelinating process?

Answer 3

1) Myelin breakdown associated with lymphocyte and macrophage infiltration of affected area- plaque
2) Proliferation of astrocytes – gradual infiltration of astrocytes intodemyelinating area
3) Reduced cellularity, astrocyte reduce in size

Question 4

response to injury in CNS?

Answer 4

Absent/slow regeneration-blood brain barrier
• Ineffective phagocytosis
• Myelin debris persists
• Astrocyte scarring

Question 5

response to injury in PNS?

Answer 5

Rapid regeneration
• Macrophages migrate from blood
• Complete interruption of blood nerve barrier

Question 6

Wallerian degeneration (anterograde)?

Answer 6

degeneration of axon distal to site of injury

Question 7

PNS anterograde degeneration?

Answer 7

degeneration takes a few days

-Dedifferentiation of Schwann cells and alignment.\

Question 8

CNS anterograde degeneration?

Answer 8

degeneration takes several weeks

-Loss of axon contact initiate apoptotic cell death

Question 9

chromatolysis?

Answer 9

loss of Nissl substance from cell
body
• 1-2 days after injury
– Changes in cell body are
proportionate to:
• amount of axoplasm lost
from injury
– large amount =CELL DEATH

Question 10

Guillian barre?

Answer 10

damage to the schwann cells

Nerve fibers - Large,accumulation of
lymphocytes,,macrophages and,plasma cells

Ascending muscle,loss of muscle co–ordination &
cutaneous sensation

Question 11

The autonomic nervous system innervates what tissues?

Answer 11

1. smooth muscle
2. cardiac muscle
3. glands

Question 12

What are the two major divisions of the autonomic nervous system?

Answer 12

the sympathetic and parasympathetic

Question 13

functions of the sympathetic nervous system?

Answer 13

fight, flight, or freight mode

Question 14

function of the parasympathetic NS?

Answer 14

rest and digest mode

Question 15

What are somatic motor neurons?

Answer 15

One long, heavily myelinated axon extending from the CNS to the effector

Question 16

autonomic motor neurons?

Answer 16

Two Neuron System
•A lightly myelinated preganglionic neuron with the cell body in the CNS
•An unmyelinated postganglionic neuron with the cell body in autonomic ganglion in the PNS

Question 17

Where are parasympathetic ganglia found?

Answer 17

near or in the walls of target organs

Question 18

Where are the sympathatic ganglia found?

Answer 18

lateral to the spine

skull to the coccyx

Question 19

where are the preaortic ganglia found?

Answer 19

The abdomen