Nervous System, Vision & Muscle Lecture Review

These flashcards cover key concepts about the nervous system, vision, and muscular system based on the provided lecture notes.

Potassium Leak Channels

Non-gated channels that allow K+ ions to flow out of the cell, helping to create a negative resting membrane potential.

Resting Membrane Potential

The stable, negative electrical charge difference (-50 to -75 mV) across the plasma membrane of inactive cells, preparing them for action potentials.

Depolarization

A shift in the neuron's polarity that makes the inside of the cell more positive.

Hyperpolarization

A shift in the neuron's polarity that makes the inside of the cell more negative.

Sodium-Potassium Pump

A form of active transport that moves 3 Na+ ions out and 2 K+ ions into the cell, using ATP to maintain the electrochemical gradient.

Flux

The rate of movement of a substance between compartments.

Ligand-Gated Channels

Transmembrane proteins that open a central pore in response to chemical messengers (ligands), converting chemical signals into electrical signals.

Action Potential

A rapid rise and fall in voltage or membrane potential across a cellular membrane, initiated when a graded depolarization reaches the threshold.

Electrochemical Gradient

A gradient that drives the movement of ions across a membrane, influenced by both electrical and chemical factors.

Photoreceptors

Cells in the retina that detect light and convert it into electrical signals for visual interpretation.