Resting and Action Potential

Question 1

Resting Potential

Answer 1

Membrane voltage of a resting cell, negative charge

Question 2

Levels of K+ and Na+Cl- at Resting Potential

Answer 2

Hi K+ on the inside and hi Na+Cl- on the outside

Question 3

Why does K+ move to the inside

Answer 3

Because of its hi-concentration and hi permeability, it moves in to balance the negative charge of the large proteins that can’t leave the cell

Question 4

Na+

Answer 4

Not very permeable and has to be pumped out

Question 5

Voltage gated Na+ Channel

Answer 5

an innovation that excitable cells have, has the activation gate and the inactivation gate

Question 6

Activation Gate

Answer 6

Closed at RP

Question 7

Inactivation Gate

Answer 7

Open at RP when the surrounding membrane depolarizes , allowing Na+ to rush in and create an AP

Question 8

Depolarizes

Answer 8

becomes less negative on the inside

Question 9

Axon Hillock

Answer 9

Action potentials normally start here

Question 10

Threshold

Answer 10

If depolarization reaches this, an AP is irreversibly fired

Question 11

Schwann Cells

Answer 11

Myelinated axons outside brain and spinal cord

Question 12

Oligodendrocytes

Answer 12

Myelinate in CNS

Question 13

What happens at threshold

Answer 13

Activation gate of V-gated Na+ channel opens and lets Na+ rush in and discharge membrane voltage

Question 14

Nodes of Ranvier

Answer 14

Space between myelin, bare membrane, where AP occurs

Question 15

Unmyelinated axons

Answer 15

APs flow smoothly towards synapse

Question 16

Myelinated axons

Answer 16

Aps skip from node to node, faster