Physiology - Intro to Neurons

Question 1

What is the name of the site of imitation of the ‘all or none’ action potential?

Answer 1

Axon hillock

Question 2

What is a pseudounipolar neurone?

Answer 2

One that splits to have two axons

Question 3

Unipolar neurons have no dendrites. T/F?

Answer 3

T - just axon

Bipolar/multipolar have dendrites

Question 4

What influx/efflux of ions are responsible for action potential upstroke and downstroke?

Answer 4

Upstroke - influx of Na+

Downstroke - efflux of K+

Question 5

What does length constant (lambda) mean?

Answer 5

Length constant is length a potential can travel before it disappears

Question 6

Match:

Schwann cell
Oligodendrocyte
Many surround single axon 
One surround many axons
Found in CNS
Found in PNS

Answer 6

Schwann cell
PNS
Many surround single axon

Oligodendrocyte
One surrounds many axons
CNS

Question 7

What is an axodendritic synapse?

Answer 7

Axon to dendrite synapse

Question 8

In the CNS what is the most common transmitter to cause an excitatory and inhibitory synapse?

Answer 8

Excitatory - glutamate

Inhibitory
- GABA or glycine

Question 9

What is the difference between ionotropic and metabotropic post synaptic receptors?

What type has a quicker response?

Answer 9

Ionotropic
= receptor is channel itself
= quicker response

Metabotropic
= receptor signals other channels