Neuron Signaling and Sodium-Potassium Pump

These flashcards focus on essential vocabulary and concepts related to neuronal signaling and the sodium-potassium pump, vital for understanding membrane potential and action potentials.

Sodium-Potassium Pump

A protein pump that moves sodium (Na+) out of the cell and potassium (K+) into the cell, helping to maintain membrane potential.

Active Transport

The movement of ions across a cell membrane from a region of lower concentration to a region of higher concentration, requiring energy (ATP).

Membrane Potential

The difference in charge between the outside and inside of a cell, critical for neuron signaling.

Depolarization

The process during an action potential when the inside of the neuron becomes more positive, as Na+ ions rush in.

Repolarization

The phase of an action potential where the membrane potential returns to a negative value after depolarization.

Threshold

The critical level (-55 mV) that must be reached for an action potential to be initiated.

Hyperpolarization

A phase during an action potential when the membrane potential becomes more negative than the resting potential.

Leakage Channels

Ion channels that allow specific ions (such as K+) to move in and out of the cell freely, contributing to the resting membrane potential.

Neurotransmitters

Chemical messengers that transmit signals from one neuron to another across synapses.

ATP Hydrolysis

The process of breaking down ATP into ADP and phosphate, providing energy for cellular processes, including the sodium-potassium pump.

Resting Potential

The electrical potential difference across the membrane of a neuron at rest, typically around -70 mV.

Extracellular Space

The environment outside of a cell, containing a high concentration of sodium ions during the resting state of a neuron.

Intracellular Space

The fluid inside the cell, containing a high concentration of potassium ions during the resting state of a neuron.

Action Potential

A rapid rise and fall in membrane potential that occurs when a neuron is stimulated, leading to nerve impulse transmission.

Neuromuscular Junction

The synapse where a motor neuron communicates with a muscle fiber, involving neurotransmitter release.