Nerve

Question 1

What does the soma of a neuron contain?

Answer 1

Rough endoplasmic reticulum (called Nissl substance or Nissl bodies)

Question 2

What do dendrites do?

Answer 2

Transmit information towards the soma

Question 3

What do axons do?

Answer 3

Arise from the axon hillock and transmit information away from the soma

Question 4

What are the characteristics of dendrites?

Answer 4

Many per cell
Irregular profiles (dendritic spines)
Tapered
Highly branched
Not myelinated
Contains ribosomes and RER
More neurotubules than neurofilaments

Question 5

What are the characteristics of axons?

Answer 5

One per cell
Smooth profiles
Uniform diameter
Relatively straight
Few branches
Often myelinated
No RER, ribosomes
More neurotubules

Question 6

What are neuroglia?

Answer 6

Support cells of the CNS/PNS

Question 7

What do oligodendrocytes do?

Answer 7

Form the myelin sheath

Question 8

What are the two type of astrocytes?

Answer 8

Fibrous astrocytes

protoplasmic astrocytes

Question 9

Where are fibrous astrocytes?

Answer 9

Between myelinated nerve fibers (white matter)

Question 10

Where are protoplasmic astrocytes?

Answer 10

Surround sonata and dendrites (grey matter) and participate in metabolic exchange

Question 11

Where are ependymal cells?

Answer 11

Ependymal cells line brain vesicles

Question 12

What do microglial cells do?

Answer 12

Act as brain macrophages

Question 13

What do schwann cells do in the PNS?

Answer 13

Form the myelin sheath

Question 14

What do satellite cells do in the PNS?

Answer 14

Surround somata in ganglia

Equivalent of astrocytes in the CNS

Question 15

What’s the main function of astrocytes?

Answer 15

Structural support, repair processes, blood brain barrier, metabolic exchange

Question 16

What is the blood brain diffusion barrier (BBB)?

Answer 16

A specialized endothelium lining blood vessel lumens in the CNS

Question 17

How is the BBB protected from large molecules?

Answer 17

Tight junctions occur between endothelial cells to form a diffusion barrier to large molecules

Question 18

What proceses does the BBB to move specific cells across the barrier?

Answer 18

Active endo- and exocytosis vesicle pathways for specific transport

Question 19

What regions of the brain do not have BBB?

Answer 19

Choroid plexus (CSF production), pituitary gland, pineal gland and other ‘circumventricular’ organs

Question 20

Axons in the PNS are bundled into?

Answer 20

Fascicles

Question 21

Individual axons with their swan cells are surrounded by?

Answer 21

Endoneurium

Question 22

What is endoneurium?

Answer 22

Connective tissue containing collagen fibers, fibroblasts and mast cells

Question 23

What are fascicles surround by in the PNS?

Answer 23

Perineurium

Question 24

What doe the perineurium help to establish?

Answer 24

A peripheral blood-nerve diffusion barrier

Question 25

What does the perineurium actively transport?

Answer 25

Nutrients in

Waste out

Question 26

What kind of cells are in the perineurium?

Answer 26

Stratified squamous layer of ct each decent cell fused by tight junctions

Question 27

The perineurium can become thicker containing collagen and actin fibers giving it the ability to?

Answer 27

Contract

Question 28

Epineurium can often be associated with what kind of tissue?

Answer 28

Adipose tissue

Question 29

What is anterograde (Wallerian) degeneration in PNS?

Answer 29

Atonal degeneration distal to the injury site