Brain Cells Flashcards
1
Q
Account for about 90% of our brain cells
A
Glial cells
2
Q
What forms myelin
A
Oligodendrocytes
3
Q
Main types of glial cells in the CNS
A
Astrocytes, oligodendrocytes, microglia
4
Q
Form the blood-brain barrier (barrier between neuronal tissue and blood)
A
Astrocytes
5
Q
Devour and remove debris left by dead or degenerating brain cells
A
Microglia
6
Q
What is the membrane potential of a neuron?
A
-70 mV inside compared to outside
7
Q
What are the 3 phases of an action potential?
A
- Rising phase: both Na+ and K+ channels open (membrane potential increases)
- Repolarization: Na+ channels close (membrane potential decreases)
- Hyperpolarization: K+ channels close (membrane potential decreases)
8
Q
What are the Nodes of Ranvier and what happens at them?
A
They are the spaces between bits of myelin where action potentials happen
