Transmission within neurons Flashcards
1
Q
What is inside the cell?
A
Organic anions (-)
Potassium K+
Water
2
Q
What is outside the cell?
A
Sodium Na+
Chloride Cl-
Water
3
Q
Resting potential
A
-70mV
more anions inside and more cations outside
4
Q
How does a cell maintain resting potential?
A
Sodium-potassium pump
- 3 Na+ in, 2 K+ out
5
Q
What is the threshold?
A
-55mV
6
Q
What is the voltage when an action potential occurs?
A
+40mV
7
Q
Describe recovery/hyperpolarisation
A
- Sodium gates close
- Potassium gates open
- K+ floods out
- Potential at -80mV
- K+ channels close
- Sodium-potassium pump returns cell to resting potential
8
Q
What is myelin?
A
Fatty layer of insulation found around some neurons
9
Q
What is myelin made of?
A
Schwann cells and oligodendrocytes
10
Q
What speed is an action potential of non-myelinated neurons?
A
2m/s
11
Q
What speed is an action potential of myelinated neurons?
A
120m/s
