Action Potential

In a muscle cell at rest, _____ is in high concentration on the outside and ____ is at high concentration on the inside.

• Na+, K+

• K+, Na+

• Cl-, Na+

• Na+, Cl-

A reversal in membrane polarity, or when the membrane becomes less charged is termed _______.

• hyperpolarization

• repolarization

• depolarization

• threshold

The first sodium channels that open are _____ gated.

• ligand

• voltage

• mechanically

• leak channels

Na+ channels open and cause more Na+ channels to open, this causes _______ channels to open, this is ______ feedback.

• voltage gated Na+, positive

• ligand gated Na+, positive

• voltage gated K+, positive

• voltage gated K+, negative

During resting membrane potential and repolarization, the outside of the membrane is _____ _____ when compared to the inside of the cell.

• more positive

• more negative

• less negative

• less positive

During resting membrane potential the outside charge is due to ______, but during repolarization, the charge on the outside is to due to the _____.

• Na+, K+

• K+, Na+

• K+, Ca+

• Ca+, K+

During the absolute, refractory period _____.

• a muscle can only be stimulated again if the impulse is greater than the first

• in no way possible can another action potential be generated

• an action potential occurs completely or not at all

• the minimum amount is met to create an action potential

What is the minimum amount necessary to create an action potential?

• threshold

• subthreshold

• hyperpolarization

• repolarization

Calcium at the neuron_____, while calcium at the muscle ____.

• causes exocytosis of vesicles, binds to tropononin tropomyosin complex to expose actins active sites

• binds to troponin to expose actins active sites, causes exocytosis of vesicles

• causes bone density, binds to troponin to expose actins active sites

• causes exocytosis of vesicles, binds to tropomyosin to expose actins active sites

The sodium potassium pump is inactive during an action potential.

• True

• False