Resting Membrane Potential

Question 1

1 of the general principles of ion movement

Answer 1

Ions will flow from an area of high concentration to an area of low concentration

Question 2

2 of the general principles of ion movement

Answer 2

Ions will flow toward an area of opposite charge and away from an area of like charge.

Question 3

What is information transmission?

Answer 3

• Information is carried by waves of ions moving across the neuron cell membrane
• Small, fat-soluble molecules are able to pass through the cell membrane (O2, CO2, ETOH).
• Charged molecules must pass through special channels

Question 4

Leaked channels are?

Answer 4

Always open

-Allow diffusion of a small number of ions all the time

Question 5

Gated channels are?

Answer 5

Opens only in response to a specific stimulus

• closes when the stimulus is removed or after a set time
• Open at different rates
• Ions can move across the cell membrane only when the gate is open

Question 6

Selectively permeable is what?

Answer 6

Only a special kind of ion can pass through

Question 7

Gated channels - Modality - Gated

Answer 7

Respond to sensory receptor activation by a mechanical (pressure, sound), thermal, chemical, or electromagnetic stimulus (light/vision)

Question 8

Gated channels - Ligand - Gated

Answer 8

Respond to the binding of a neurotransmitter or other Ligand to the receptor on a post-synaptic membrane.

Question 9

Gated channels - Voltage - Gated

Answer 9

Respond to a change in voltage across the cell membrane

Question 10

Electrical Potential

Answer 10

Three types necessary in neurons for information transmission

• Resting membrane potential
• Local (graded) potential
• Action potential

Question 11

What is resting membrane?

Answer 11

Difference in voltage across the cell membrane when the neuron is not transmitting information

Question 12

What is resting membrane potential - what is going in and out of the cell?

Answer 12

Na+ - K+ pump pumps Na+ out of and K+ into the cell

• Pump is always on
• Pump requires ATP to function
• Diffusion

Question 13

What does the resting membrane potential do?

Answer 13

• Pump helps to return the membrane to RMP at the end of the action potential.
• Pump helps prepare the neuron for the next stimulus.
• Without the pump the neuron cannot transmit information to the next cell.

Question 14

What happens during a resting membrane potential - what channels are open/closed?

Answer 14

• Leak channels are open
• Gated N+ channels are closed
• Gated k+ channels are closed
• Na+-K+ pump is on
• Large negative charged ions located in the neuron help to maintain electrical gradient

Question 15

Negative ions are called?

Answer 15

anions

Question 16

Positive ions are called?

Answer 16

cations

Question 17

What happens during resting membrane potential part II

Answer 17

Na+ out > K+ in + large anions in lots of positive charge outside of the cell and a relative negative charge inside of the cell.
-The difference in voltage is know was the charge differential or the resting membrane potential

Question 18

What is the resting membrane potential for humans?

Answer 18

• 70mV

- More negative inside the cell then outside