Resting Membrane Potential and Action Potential Overview

Resting Membrane Potential

Electrical potential difference across a cell at rest.

Key Ions

Na+ and K+ ions maintain resting membrane potential.

Selective Permeability

Cell membrane allows specific ions through ion channels.

Nernst Equation

Calculates equilibrium potential for a specific ion.

Goldman Equation

Calculates overall resting membrane potential considering all ions.

Action Potential

Electrical signal transmission initiated by depolarization.

Depolarization Event

Membrane potential rises above threshold to trigger action potential.

Voltage-Gated Ion Channels

Proteins that allow ion flow during action potential.

Threshold Potential

Minimum membrane potential to open voltage-gated channels.

Self-Sustaining Depolarization

Continued depolarization once threshold is reached.

All-or-Nothing Principle

Action potential amplitude remains constant regardless of stimulus strength.

Propagation of Action Potential

Transmission of action potential along the neuron.

Excitable Cells

Cells capable of generating action potentials, e.g., neurons.

Ion Channels

Proteins that regulate ion flow across membranes.

Concentration Gradient

Difference in ion concentration across the membrane.

Electrical Gradient

Difference in charge across the cell membrane.

Equilibrium Potential

Membrane potential where ion movement is balanced.

Membrane Permeability

Ability of membrane to allow ions to pass.

Neurons

Nerve cells that transmit electrical signals.

Muscle Cells

Cells that contract and generate force via action potentials.

Cellular Physiology

Study of cell functions and processes.

Resting State

Condition of a neuron before action potential initiation.

Ion Influx

Movement of ions into the cell during depolarization.