Neurophysiology: Resting Membrane Potential

Flashcards covering key vocabulary and concepts related to neurophysiology, specifically focusing on the resting membrane potential.

Membrane potential

Potential difference across a membrane due to unequal charge distribution.

Resting membrane potential

Membrane potential of an undisturbed cell; starting point where the inside is slightly negative compared to the outside.

Graded potential

Temporary, localized change in resting potential produced by a typical stimulus that decreases with distance.

Action potential

Electrical event that involves one location on the axon membrane and spreads along the axon toward axon terminals.

Presynaptic cell

The neuron that releases neurotransmitters into the synapse.

Neurotransmitter

Chemicals released by the presynaptic cell that bind to receptors on the postsynaptic cell membrane.

Resting membrane potential contributors

Extracellular fluid high in sodium and chloride ions, cytosol high in potassium ions and negatively charged proteins.

Passive forces

Natural diffusion forces that help maintain resting membrane potential through leak channels.

Leak channels

Passive membrane channels that are always open, allowing specific ions to diffuse through.

Sodium-potassium exchange pump

Active transport mechanism that removes 3 Na ions from the cell and adds 2 K ions, maintaining stable resting potential.

Chemical gradient

Concentration gradient for an ion across the plasma membrane.

Electrical gradient

Difference in electric potential caused by the attraction of opposite charges or repulsion of like charges.

Electrochemical gradient

Form of potential energy determined by the combination of an ion's chemical and electrical gradients.