Excitable cells 5: Anatomy and function of the nervous system intro

Question 1

What are glia? 3 major classes of glial cells

Answer 1

Astrocytes

• cellular extentions interact with synapses and blood vessels
• control composition of extracellular space to allow neuronal function
• form scar tissue after injury

Microglia
- Brain macrophages. Clear infections and debris

Oligodendrocytes
- Cellular extensions form insulation myelin sheath around tissue in CNS

Question 2

Myelination in CNS versus PNS

Answer 2

CNS - oligodendrocytes (one can myelinate several internodes)
PNS - Schwann cells (one per internode)

Question 3

Human-worm nervous system similarities

Answer 3

Body-long axis has chain of neurons from which nerve fibres reach body extremities

Motor neurones concentrated ventrally

Sensory fibres concentrated dorsally and in the head

Question 4

3 types of nervous system in mammals

Answer 4

Sensory
Visceral (autonomic)
Motor

Question 5

4 main structural areas during development of rostral neural tube in developing embryo

Answer 5

Forebrain
Midbrain
Hindbrain
Brain-stem

Question 6

Difference between rodent and human brain at cerebral cortex junction angle

Answer 6

Human is at 90 degrees to spinal cord

Question 7

Structure of spinal cord

Answer 7

3 layers comprised -: meninges

• pia
• arachnoid
• dura mater

Question 8

Basic structure of the human brain
- Diagram needed
Sagital and Coronal cross section

Answer 8

Frontal lobe
Temporal love
Cerebellum
Pons
Medulla Oblongata

Question 9

% of neurones in the cerebral cortex in humans

Answer 9

25%

Question 10

3 types of neurones

Answer 10

Sensory: touch, smell, taste, temperature
Motor: control muscle action (directly or indirectly)
Inter-neuron: connect one neuron to another neuron