1030- Neurons and glia

Question 1

What can increase the rate of conduction across a neuron ?

Answer 1

Myelination

Question 2

3 layers of the peripheral nervous system

Answer 2

endoneurium, perineurium and epineurium

Question 3

endoneurium

Answer 3

delicate connective tissue layer surrounding axon and associated schwann cells

Question 4

perineurium

Answer 4

connective tissue layer surrounding axons forming fascicles.

Question 5

epineurium

Answer 5

contains blood vessels and forms the nerve itself , connective tissue layer surrounds individual fascicles.

Question 6

fascicles

Answer 6

bundles of structures

Question 7

convergence

Answer 7

where multiple presynaptic neurons join onto one post synaptic neuron

Question 8

divergence

Answer 8

when the axons of one presynaptic neurons diverge into many branches which end on many different post synaptic neurons.

Question 9

function of neuroglia

Answer 9

to provide support for neurons

Question 10

Major CNS classes of neuroglia

Answer 10

astrocytes, oligodendrocytes, ependymal cells, microglia

Question 11

Major PNS classes of neuroglia

Answer 11

schwann cells

Question 12

What do astrocytes look like and where are they found

Answer 12

star shaped cells and the majority of them are found in the brain

Question 13

function of astrocytes

Answer 13

fills the spaces in between neurons , support of the blood brain barrier and forms glal limitants

Question 14

homeostatic function of astrocytes

Answer 14

regulates water, potassium and neurotransmitter levels, and inhibits axon regeneration

Question 15

oligodendrocytes

Answer 15

branched cells which inhibit axon regeneration and myelinates the glia

Question 16

Where are ependymal cells found?

Answer 16

found in the brain ventricles, spinal cord and central canal.

Question 17

What are microglia and what do they respond to:

Answer 17

specialised macrophages and they reponsond to inflammation , phagocytose necrotic tissue, microorganisms and foreign substances which invade the CNS.

Question 18

How is the myelin sheath formed ?

Answer 18

schwann cells wrap around one part of the axon which they squeezes the cytoplasm out causing multiple layers of the cell membrane to wrap around the axon.

Question 19

What do schwann cells promote?

Answer 19

Axon regeneration