Understanding Resting Membrane Potential

What is the primary cause of the potential difference across a cell membrane?

• The thickness of the membrane

• The temperature of the cell

• The presence of organic molecules

• The distribution of ions

Which ion is primarily responsible for creating the diffusion potential in the example discussed?

• Sodium

• Calcium

• Chloride

• Potassium

What happens when the concentration and electrical gradients balance each other for an ion?

• The ion is expelled from the cell

• The ion becomes neutral

• The ion reaches electrochemical equilibrium

• The ion continues to diffuse

What would the membrane potential be if the membrane were only permeable to sodium?

• Equal to the equilibrium potential of sodium

• Equal to the equilibrium potential of potassium

• Zero

• Positive

How does permeability affect the resting membrane potential?

• It only affects non-excitable cells

• It determines how close the potential is to an ion's equilibrium potential

• It makes the potential more positive

• It has no effect

Why is the inside of a nerve fiber membrane more negative?

• Because of the presence of more calcium ions inside

• Because of the higher permeability to potassium

• Due to the presence of more sodium ions inside

• Due to the absence of organic anions

What role do leak channels play in the resting membrane potential?

• They allow ions to move against their gradient

• They allow ions to diffuse along their gradient

• They prevent ion movement

• They only allow sodium ions to pass

What is the function of the Sodium-Potassium ATPase pump?

• To increase the membrane potential

• To equalize ion concentrations

• To decrease the membrane potential

• To maintain the concentration gradient

What is the significance of the charge separation at the membrane?

• It prevents ion movement

• It stabilizes the cell structure

• It allows for the generation of action potentials

• It makes the cell non-excitable

What happens to the membrane potential in excitable cells?

• It becomes more positive

• It can change to create graded or action potentials

• It remains constant

• It becomes more negative