Nervous System 2 Flashcards
What are bundles of nerve fibres called?
fascicles
What forms myelin
Schwann cells and oligodendrocytes
Where does action potential occur?
Nodes of Ranvier
What makes up a single segment of myelin sheath?
Schwann cell
What is grey matter?
contains most of neuronal cell bodies and dendrites
What is white matter?
Contains most of the axons (myelinated)
What is the most abundant cells in the CNS?
Glial cells @ 90%
Where are ependymal cells found?
lining ventricles and spinal canal of spinal cord
What is the function of ependymal cells?
- Secrete CSF
2. Possess cilia to help with flow
What do ependymal cells look like?
simple, cuboidal, ciliated cells
What is the most abundant glial cell?
Astrocytes
What is the function of astrocytes?
- Control blood brain barrier (BBB)
2. Metabolic support
What are microglia?
Resident immune cells of the brain
What are the different shapes of microglia?
Ramified
Amoeboid
What is the function of microglia?
- Release nerve growth factors in resting state (stationary)
- Activated by infection/injury:
a. Alter shape (amoeboid)
b. Become phagocytic
c. Release chemicals