AP Biology Cell communication

Front

What is the role of a ligand in cell communication?

Back

A ligand is a signaling molecule that binds to a specific receptor on a target cell, initiating a response.

Front

What effect does a mutation in the receptor gene have on ligand binding?

Back

A mutation that substitutes a charged amino acid for a nonpolar amino acid in the ligand binding site can reduce the binding affinity of the ligand to its receptor.

Front

What is a ligand-gated ion channel?

Back

A ligand-gated ion channel is a type of membrane protein that opens or closes in response to the binding of a ligand, allowing ions to flow across the membrane.

Front

What are second messengers in cell signaling?

Back

Second messengers are small, water-soluble molecules that relay signals received at receptors on the cell surface to target molecules inside the cell.

Front

How do second messengers move within the cell?

Back

Second messengers can rapidly move throughout the cell by diffusion due to their small size and water-solubility.

Front

What is direct cell communication?

Back

Direct cell communication occurs when cells physically interact with each other, such as white blood cells sharing antigen information.

Front

What is the function of a protein kinase?

Back

A protein kinase transfers phosphate groups from ATP to specific proteins, which can alter the activity of those proteins.

Front

What is the significance of receptor-ligand binding in cell signaling?

Back

Receptor-ligand binding is crucial for initiating cellular responses to external signals, influencing processes like growth, metabolism, and immune responses.

Front

What are the two main types of cell signaling?

Back

The two main types of cell signaling are direct signaling (cell-to-cell contact) and indirect signaling (via ligands and receptors).

Front

What is the difference between a primary messenger and a secondary messenger?

Back

A primary messenger is the initial signaling molecule (like a hormone) that binds to a receptor, while a secondary messenger is a molecule that transmits the signal inside the cell.