Cells of the Nervous System 2

Question 1

What is neuronal integration?

Answer 1

Integration of competing inputs in the postsynaptic neurone

Question 2

3 types of synapse and their nature?

Answer 2

Axo-dendritic - excitatory
Axo-somatic - inhibitory
Axo-axonic - modulatory

Question 3

Support cells of CNS?

Answer 3

Astroglia
Oligodendroglia
Microglia
Ependymal cells

Question 4

Support cells of PNS?

Answer 4

Schwann cells

Satellite glia

Question 5

Features of astroglia?

Answer 5

Star-shaped
Most abundant CNS cell type
3 types
Numerous intermediate filament bundles
Gap junctions

Question 6

3 types of astroglia?

Answer 6

Fibrous (white matter)
Protoplasmic (grey matter)
Radial

Question 7

Functions of astroglia?

Answer 7

Scaffold for neuronal migration and axon growth during development
Formation of blood-brain barrier and brain-CSF barrier
Transport of substances from blood to neurones
Removal and degradation of neurotransmitters
Neuronal-glial/glial-neuronal signalling

Question 8

Oligodendroglia features?

Answer 8

Small spherical nuclei
Prominent ER and Golgi
No intermediate filaments
Highly metabolically active

Question 9

Oligodendroglia function? (crucial)

Answer 9

Production/maintenance of myelin sheath

Question 10

Myelin features?

Answer 10

Lipid-rich insulating membrane
Up to 50 lamellae
Dark and light bands
Highly susceptible to damage

Question 11

Microglia features and types?

Answer 11

Macrophages
Dense lysosomes, lipid droplets and residual bodies
3 categories based on morphology, Resting Ramified, Rod-like, Activated

Question 12

Functions of microglia?

Answer 12

Macrophage population of CNS
Immune surveillance and antigen presentation
First cells to react to infection/damage

Question 13

What are ependymal cells and where do you find them?

Answer 13

Epithelial-type cells which line ventricles and central canal of spinal cord

Question 14

Ependymal cell features?

Answer 14

Apical microvilli and cilia
Prominent gap junctions between cells
No tight junctions

Question 15

Peripheral nervous system support cell types?

Answer 15

Schwann cells

Satellite cells

Question 16

What are Schwann cells and what do they do?

Answer 16

Produce myelin - only one myelin sheath per cell
Envelope axons of sensory and motor neurones in the PNS
Also perform functions of astrocytes
Promote axon regeneration

Question 17

What are satellite cells and what do they do?

Answer 17

Provide metabolic support
Surround neuronal cell bodies in spinal ganglia
Perform functions of astrocytes from GREY matter of the CNS (protoplasmic)

Question 18

Two types of oligodendroglia and where are they found?

Answer 18

Interfascicular - found in rows along axon tracts

Perineuronal - found in association with neuronal cell bodies