AP Biology Unit 4 Review

Front

What is a signal transduction pathway?

Back

A series of molecular events and chemical reactions that lead to a cellular response after a signal (like a hormone) binds to a receptor.

Front

What is the role of cell membrane receptors in signal transduction?

Back

Cell membrane receptors bind to specific ligands (signals) and initiate a response within the cell, often activating a cascade of intracellular events.

Front

What is a mutation in a receptor protein?

Back

A change in the DNA sequence of a receptor protein that can alter its structure and function, potentially affecting cell signaling.

Front

How do cancerous cells differ in their cell cycle compared to healthy cells?

Back

Cancerous cells typically have a much shorter cell cycle, allowing them to divide and proliferate uncontrollably.

Front

What is density-dependent inhibition?

Back

A regulatory mechanism where cell growth and division are inhibited when cells become crowded, which cancerous cells often bypass.

Front

What is a secondary messenger in cell signaling?

Back

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

Front

What is the significance of ligand binding to a receptor?

Back

Ligand binding is crucial for activating the receptor, which triggers the signal transduction pathway and leads to a cellular response.

Front

What is transcription in the context of signal transduction?

Back

The process by which a cell converts a segment of DNA into RNA, often resulting in the production of proteins that carry out specific functions.

Front

What is a phosphorylation cascade?

Back

A series of events where one enzyme phosphorylates another, leading to a chain reaction that amplifies the signal within the cell.

Front

What happens when a receptor protein is mutated?

Back

A mutation can alter the receptor's shape or function, potentially reducing the cell's ability to respond to signals.