cell communication

Action Potential

A quick electrical change in a nerve cell that travels along the cell membrane when a stimulus (like a signal) triggers the cell.

Circadian Rhythm

The natural cycle of about 24 hours that controls things like sleep and wakefulness in most organisms, even without sunlight.

Cytokinin

A plant hormone that helps with cell growth and stops plants from aging too quickly. Works with auxin to help plants grow and stay healthy.

Ethylene

A gas hormone in plants that helps fruit ripen and leaves fall off.

G protein-coupled receptor

A protein on a cell's surface that, when it binds with a signal (like a hormone), activates a G protein to send a signal inside the cell.

Gibberellin

A plant hormone that promotes growth, helps seeds germinate, and helps flowers develop.

Heat-shock protein

Proteins that help protect other proteins when the cell gets too hot.

Acetylcholine

A common chemical messenger (neurotransmitter) used in the brain and nervous system to send signals between nerve cells. It can either speed up or slow down nerve signal transmission.

Auxin

A plant hormone that helps plants grow by stretching their cells. It helps with things like making plants grow toward light (phototropism) and helps flowers grow.

Biofilm

A group of microorganisms that work together by sending signals to each other, usually forming a sticky layer, like plaque on teeth.

Intracellular Receptor

A receptor inside a cell that binds with signaling molecules (like hormones) to cause changes inside the cell.

Ligand

A molecule that attaches to a receptor and causes a response.

Luciferase

An enzyme that makes light in organisms like fireflies.

Neurotransmitter

A chemical messenger that carries signals between nerve cells.

Phosphorylation

Adding a phosphate group to a molecule, often to activate or change its function (like turning it on).

Photoperiodism

A plant's response to the amount of light and darkness it gets, like when flowers bloom at specific times.

Protein Kinase

An enzyme that adds a phosphate group to a protein to change its function.

Protein Phosphatase

The way bacteria communicate to coordinate behavior based on how many of them are in an area.

Quorum Sensing

The way bacteria communicate to coordinate behavior based on how many of them are in an area.

Salicylic Acid

A plant hormone that helps plants defend against diseases. It's also the active ingredient in aspirin.

Scaffolding Protein

A large protein that helps organize and link other proteins to make signaling inside the cell more efficient.

Second Messenger

A small molecule (like calcium or cAMP) inside the cell that helps carry a signal from the receptor to other parts of the cell.

Senescence

The aging process in cells and organisms.

Signal Transduction Pathway

The series of steps that a cell uses to turn an external signal into a response.

Statolith

A special particle in plants that helps detect gravity, helping the plant know which way to grow.