Physiology: Neurons to Networks

Question 1

Name the non-neuronal structures and functions.

Answer 1

• Ependyma: regulates transfer of substances between brain and cerebrospinal fluid
• Meninges: dura, arachnoid, pia
• Glia
- Microglia: phagocytose dead tissue and debris, immune response
- Astrocytes: 20-50% of volume of most brain areas.
- Oligodendrocytes: form myelin in the CNS

Question 2

List the functions of astrocytes.

Answer 2

• Regulate flow of small molecules and ions between blood and neurons (BBB)
  
  • Structural scaffold
  • Surround nodes of Ranvier, regulate ECF [K+]
  • Ensheath synapses, dendrites and neuronal cell bodies - metabolize and release neurotransmitters
    Connect to one another by gap junctions, forming a syncytium