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Flashcards in Action Potentials Deck (28)
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1
Q

A rapid depolarization is followed by a ____

A

rapid repolarization

2
Q

Neuron re-polarizes at about ___ mV

A

+20 mV

3
Q

Depolarization is caused by what?

A

Increase in cytosolic Na concentraion

4
Q

Typical resting potential is what?

A

-65 mV

5
Q

At +20 mv, the Na ____ force is outward while the Na ___ force is inward.

A

electrical

concentration

6
Q

At +20 mv Sodium channels ____ to keep pumping out sodium using electrical force.

A

close

7
Q

To repolarize what direction does K+ flow?

A

outward

8
Q

At +20mv, what direction is the K+ chemical and electrical force?

A

Both are outward

9
Q

Once at -65 mV concentration what direction is the K+ chemical and electrical force?

A

The electrical force is inward but the concentration force is outward.

10
Q

At -65 mV concentration what happens to the K+ channels?

A

The K+ channels close

11
Q

What structure allows for a change in membrane potential triggering an action potential?

A

Voltage gated channels

12
Q

What is the threshold for action potential?

A

-55mV

13
Q

What is the period in which a neuron is inactive and will remain inactive until the membrane is at resting potential

A

Refractory period

14
Q

What is it called when a current enter and spreads throughout the membrane

A

Electron-tonic conduction

15
Q

Propagation speed is dependent on what two factors?

A

mylination and diameter size

16
Q

Which axon will have a high propagation speed? The one with the larger diameter or smaller diameter?

A

The one with larger diameter

17
Q

The Axon hillock originates what?

A

depolarization

18
Q

Axon specifically identify what?

A

Pathways of communication

19
Q

Sodium channels have two gates ____ and ____

A

Inactivation gate and Activation gate

20
Q

At -65mv the sodium inactivation gate is ___

A

open

21
Q

At -65mv the sodium activation gate is ___

A

Closed

22
Q

At threshold (-55mv) the sodium activation gate is ___

A

Open

23
Q

At threshold (-55mv) the sodium inactivation gate is ___

A

Open

24
Q

At +20mv the sodium activation gate is ___

A

Open

25
Q

At +20mv the sodium inactivation gate is ___

A

Closed

26
Q

At re-polarization the sodium inactivation gate ___

A

opens

27
Q

At re-polarization the sodium activation gate ___

A

Closes

28
Q

What is the function of an action potential?

A

It is to communicate with other neurons