Neural Signalling

Which of the following statements regarding resting membrane potential is CORRECT?

• The sodium-potassium pump generates only about -1 to -3mV of the resting membrane potential.  

• The resting membrane potential remains constant due to the establishment of dynamic equilibrium. 

• The resting membrane potential is closer to the equilibrium potential of K⁺ as opposed to Na⁺, because the membrane is more permeable to K⁺ than Na⁺.

The operation of the sodium-potassium "pump" moves

• sodium and potassium ions into the cell.

• sodium and potassium ions out of the cell.

• sodium ions into the cell and potassium ions out of the cell.

• sodium ions out of the cell and potassium ions into the cell.

Tags

NGSS.HS-LS1-3

A cation that is more abundant as a solute in the cytosol of a neuron than it is in the interstitial fluid outside the neuron is

• HCO3-.

• Cl-.

• Na+.

• K+.

Tags

NGSS.HS-LS1-3

The membrane potential that exactly offsets an ion's concentration gradient is called the

• graded potential.

• threshold potential.

• equilibrium potential.

• action potential.

ATP hydrolysis directly powers the movement of

• K+ out of cells.

• Na+ out of cells.

• Na+ into cells.

• Ca2+ into cells.

Opening all of the sodium channels, with all other ion channels closed - which is an admittedly artificial  setting - on an otherwise typical neuron should move its membrane potential to

• -90 mV.

• -70 mV.

• +30 mV.

• +62 mV.

Tags

NGSS.HS-PS3-5

The resting membrane potential is about...

• -70mV

• -50mV

• 35mV

• 70mV

Na⁺ - K⁺ pump

I. Does not need energy in the form of ATP to work

II. Expels 3 Na⁺ for every 2K+ ions imported

III. Works against a concentration gradient

IV. Maintains resting potential

• All are correct

• Only II and III are correct

• Only I and III are correct

• Only I is incorrect

Tags

NGSS.HS-LS1-3

Which of the following diagram illustrates the distribution of Na⁺ and K^{+ i}ons in a section of non-myelinated axon which is at resting potential?

• 
• 
• 
• 

When Na⁺ is diffusing in

• the membrane potential increases

• the membrane potential decreases