12.7- Neuron Physiology

Question 1

Voltage

Answer 1

The amount of difference in electrical charge between two areas

Question 2

Current

Answer 2

The movement of charged particles across the barrier that represents this charge difference. Increased movement of charged particles = greater current.

Question 3

Resistance

Answer 3

The opposition to the movement of charged particles. This is the barrier between the charged areas.

Question 4

What is Ohm’s law?

Answer 4

Current= voltage/resistance

Question 5

What is the resting stated of the synaptic knob?

Answer 5

More Ca+ in the interstitial fluid (IF) than in the cytosol due to the Ca+ pump.

Question 6

Membrane potential?

Answer 6

The charge difference between the interstitial fluid and the cytosol of the cell.

Question 7

What is the RMP?

Answer 7

Resting membrane potential- -70mV but can range between -40 and -90 mV.

Question 8

What other than Na+, K+ and Cl- are needed to maintain RMP?

Answer 8

Negatively charged phosphate and negatively charged protein molecules.

Question 9

What assists and apposes the movement of K+ outside the neuron?

Answer 9

Chemical concentration gradient helps it, but the electrical concentration gradient resists it.

Question 10

Which directions do leaky channels direct K+ and Na+?

Answer 10

Na+ comes in and K+ goes out. These together create the RMP of -70 mV.

Question 11

Which kind of channel is more common? Na+ or K+ leaky channels?

Answer 11

K+ channels. Thus more K+ can leak out than Na+ can leak in.

Question 12

What is the primary/secondary roll of the Na+/K+ pump?

Answer 12

Primary- creates concentration gradient

Secondary- Contributes -3 mV toward RMP