Cell Signaling

Front

What is a ligand?

Back

A signal molecule that binds to a plasma-membrane protein, initiating a cellular response.

Front

What is the role of a G protein in cell signaling?

Back

A protein located on the cytoplasmic side of a membrane that relays signals from receptors to target molecules.

Front

Define paracrine signaling.

Back

A form of cell signaling where a cell produces a signal to induce changes in nearby cells.

Front

What is the function of a protein kinase?

Back

An enzyme that activates or inactivates other proteins by transferring phosphate groups to them.

Front

How do ligand-gated channels regulate ion flow?

Back

They open or close in response to the binding of a ligand, controlling the flow of specific ions across the membrane.

Front

What is a second messenger?

Back

A molecule that relays signals received at receptors on the cell surface to target molecules inside the cell.

Front

Explain the difference between endocrine and paracrine signaling.

Back

Endocrine signaling involves hormones traveling through the bloodstream to distant targets, while paracrine signaling affects nearby cells.

Front

What is autocrine signaling?

Back

A type of signaling where a cell targets itself, releasing signals that bind to its own receptors.

Front

What is juxtacrine signaling?

Back

A form of cell signaling that requires direct contact between the signaling and target cells.

Front

What is the role of cAMP in cell signaling?

Back

cAMP acts as a second messenger that transmits signals from receptors to target proteins, often activating protein kinases.