Glial cells

• Glia provide structural support in the nervous system
• Glia nourish neurons by supplying nutrients from the blood.
• Gila creates barriers between the blood and brain so toxic substances can't get in. Blood Brain barrier (BBB)
• Gila scavenge debris and dying nerve cells
• Gila provide a sheath for some neutrons to form an insulation called myelin.
• Myelin is an insulating layer an insulating layer, or sheath that forms around nerves.
• Gilal cells act to maintain an optimal environment for neuronal function. Gilal cells keep neurons safe and protected, well-supplied and free to move where they need to
• Gilal cells repair the nervous system after injuring.
• Gilal cells control the local environment of the brain (the microenvironment) around neurons. Mopping up extra ions and other chemicals like neurotransmitter chemicals to help maintain neurons in optimal state for function.
• Astrocytes are what?

  Multipurpose cells
• Astrocytes do what?

  Deliver nutrients from the blood to neurons and take waster products in the opposite direction.
• Astrocytes control what?

  Chemical environment, like ions and transmitters around neurons or the brain cells.
• Astrocytes repair what?

  scarring of nerve cells in CNS.
• Astrocytes provide what?

  Buffer reserve of "fuel" for cells as they contain glycogen so they can break down to release glucose during high period of high demand by neurons.
• What is glycogen?

  A large molecule made of glucose sub unit molecules
• Oligodendrocytes and Schwann cells provide what?

  Myelin sheath around the axon of some neurons.
• Axon is?

  Transmitter for the brain from the nerve cells.
• Microglia are what?

  Specialised immune cells making up the immune defence in CNS
• What type of WBC is Migcrogila?

  Macrophage (specialised WBC). Only present in CNS
• What do Microgila do?

  Scavenge cell debris

  • From dying neurons
  • other gilal cells
• Microglia are?

  First responders to damage of CNS
• Scavenging can be?

  Good or bad:

  • It prevents the build-up of toxic was but also contributes neurodegeneration (nerve degeneration)
• How does Microgila efficiently scan the local environment to identify insults to CNS?

  Reorganise their shape by changing their processes. However, the cell body doesn't change and it doesn't change shape.
• How does Microgila play important roles in birth and adulthood?

  Regulating the development of the brain after birth and brain plasticity in adulthood.
• What do Ependymal cells do?

  Line the brain's fluid spaces (the ventricles) to form a slight barrier between the fluid spaces and the cells while producing CSF.
• What do Ependymal cells have?

  Cilla

  • Hair-like organelles cavity of the ventricles.
• What does cillia do in the Ependymal cells? 


  Time their movement to direct CSF and influence the distribution of neurotransmitters to neurons.
• What can some Ependymal cells do?

  Divide and form neurons throughout the life of the cell. This allows neurodegeneration to occur.
• What can Ependymal support cells do? 


  Provide an environment that protects axon stumps from degeneration after damage. Ultimately allowing neuronal connections to grow and restore function. This replenishes a good amount of dead neurons
• Cell bodies synthesis and/or process proteins, lipids, etc
• Glial cells have 5 different types: astrocytes, oligodendrocytes, microglia, ependymal cells, and Schwann cells.
• Myelination involves glial cells wrapping themselves around parts of the axon and winding themselves higher and higher
• The process of myelination involves glial cells squeezing all their content out to the outermost winding so that all the inner windings of the sheet only consist of the cell membrane of the glial cells.
• The myelin sheath is a poor conductor of electricity so it is a good insulator for axons.