Neurons

Question 1

Three types of neurons

Answer 1

Sensory (afferent)
Motor (efferent)
Interneurons (connect neurons)

Question 2

Membrane Potential

Answer 2

Must be between -30 to -90 mV to be resting.
If it becomes more positive, then it is depolarized
If it becomes more negative, it is hyperpolarized

Question 3

Membrane Potential - ion flow

Answer 3

More K+ outside of the cell.

Question 4

Depolarization

Answer 4

If the neuron reaches its excitatory threshold, it will fully depolarize (generate an action potential)
Na+ channels open and the charge across the membrane reverses and becomes more positive INSIDE the cell, due to influx of Na+

Question 5

Peak Action potential and Hyperpolarization

Answer 5

At the peak of the action potential, Na+ channels will close and K+ channels will open, allowing K+ to leave the cell. This outflowing of K+ actually leads to a temporary hyperpolarization, during which the cell cannot fire (refractory period). K+ channels close, and the cell returns to its (polarized) resting state

Question 6

Saltatory conduction

Answer 6

The propagation of action potentials along myelinated axons from one node of Ranvier to the next node, increasing the conduction velocity of action potentials.

Question 7

1. Glutamate
2. GABA

Answer 7

1. Primary excitatory neurotransmitter
2. Primary inhibitory neurotransmitter