AP Bio Insta-Review Topic 4.3*: Signal Transduction

Front

What is a transcription factor?

Back

A protein that binds to specific DNA sequences, turning on or off gene expression.

Front

What is apoptosis?

Back

Programmed cell death, a process that eliminates unnecessary or damaged cells.

Front

What role do receptors play in signal transduction?

Back

Receptors are proteins that receive and transmit signals from outside the cell to initiate a response.

Front

Define signal transduction.

Back

The process by which a cell responds to external signals through a series of molecular events.

Front

What is the function of a promoter in gene expression?

Back

A DNA sequence that initiates transcription of a particular gene.

Front

What is the difference between endocrine and paracrine signaling?

Back

Endocrine signaling involves hormones traveling through the bloodstream, while paracrine signaling involves signals affecting nearby cells.

Front

What is a second messenger in signal transduction?

Back

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

Front

What is the role of G-proteins in signal transduction?

Back

G-proteins act as molecular switches that relay signals from activated receptors to other proteins.

Front

What is the significance of phosphorylation in cellular signaling?

Back

Phosphorylation modifies proteins, often activating or deactivating their function, thus regulating cellular activities.

Front

What is a ligand?

Back

A molecule that binds to a receptor to initiate a biological response.