The nervous system (organization and basic functions)

Question 1

Is hte inside or outside of the neuron cell more positive

Answer 1

outside is more positive

Question 2

Describe the sodium potassium pump

Answer 2

a pump that maintains the positive chargeoutside of the cell by pumping three sodium cells outside of the cell in exchange for pumping two potassium molecules inside of the cell.

Question 3

where is the highest concentration of sodium found…. what about potassium

Answer 3

highest concentration of sodium is outside of the cell, highest concentration of potassium is inside the cell.

Question 4

What is the resting potential of a neuron

Answer 4

-70 mV

Question 5

At what point does the cell block any further flow of potassium outside of the cell

Answer 5

when the membrane potential reaches 94mV

Question 6

if the moveent of sodium was the only ion moving through the membrane what would the inside charge of the cell be

Answer 6

+61 mV

Question 7

What is the nernst equation

Answer 7

an equation used to calculate the voltage charge for each ion (K, Na, Ca ect)

Question 8

If you are using the nerst equation and you are using the concentration of a negative ion that is moving from inside to outside of the cell the answer will be _________

Answer 8

positive

Question 9

if you are using the nerst equation and you are using the concentration of a positive ion that is moving from inside outside of the cell the answer will be _________

Answer 9

negative

Question 10

if you are using the nerst equation and you are using the concentration of a negative ion that is moving from outside to inside of the cell the answer will be _________

Answer 10

negative

Question 11

if you are using the nerst equation and you are using the concentration of a positive ion that is moving from outside to inside of the cell the answer will be _________

Answer 11

positive

Question 12

what is the nernst equation (like the actual equation not the definition)

Answer 12

61 * log (concentrtion inside/concentration outside)

answer will be positive or negative depending on charge and location flow of ion being used

Question 13

What are voltage gated pumps

Answer 13

pumps that open and close depending on the charge on the inside or outside of a cell.

Question 14

what is the ratio of potassium inside to outside

Answer 14

35:1

Question 15

The gate on the inside of the cell on the sodium channel is what kind of gate

Answer 15

inactivation gate

Question 16

the gate on the outside of the sodium channel in the cell is what gate

Answer 16

activation gate

Question 17

What is the difference between myeliinated and unmyelinated axon

Answer 17

myelinated axons allow nerve impulses to travel 300x faster than unmyelinated axons

Question 18

Why does myelin increase speed of nerve impulses

Answer 18

myelin acts as an electrical insulator and conductor of electricity.

Question 19

What are ways that excitation of membrane potential could be evoked

Answer 19

any factor that causes sodium to diffuse into the cell at a high rate. (mechanical or chemical disturbances) or electric pulses through the membrane

Question 20

What is important about the refractory period

Answer 20

occurs after action potential has been reached and the membrane become repolarized again. during this time the cell cannot be excited again.

Question 21

what ion acts as a stabilizer in the extracellular fluid and how

Answer 21

Calcium acts as a stabilizer because it can balance the positive impulse inside the cell by making the outside of the cell more positice

Question 22

procain and tetracaine

Answer 22

act on activation gates of sodim channel and make it difficult for the gates to open. This causes nerve impulses to fail to excite action potential.