AP Biology 4.1-4.3

How do cells communicate with other cells over short distances?

By direct contact or local signaling molecules.

How do cells communicate with other cells over long distance?

By hormones carried through the bloodstream.

How is the process of distance communication different from the process of communicating during cell-to-cell contact?

Direct physical contact between cells.

What is a signal transduction pathway?

A series of steps that converts a signal into a cellular response.

Why do cells use signal transaction pathways?

To receive, amplify, and respond to signals accurately.

How does a signal transduction pathway begin?

When a signaling molecule binds to a receptor.

What is the roles of protein modification in signal transduction pathways?

They activate or deactivate proteins to pass the signal.

What is the role of phosphorylation cascades in signal transduction pathways?

They amplify and transmit the signal inside the cell.

What role does the environment play in eliciting cellular responses?

It provides signals that trigger cellular responses.

How are signal transductions pathways used to influence cellular responses where there are changes in the environment?

They detect environmental changes and activate pathways to adjucts cell behavior.

How can mutations in the receptor protein or any component affect the transduction of a signal?

They can block, reduce, or misdirect the signal, disrupting the response.

How can chemicals activate a pathway?

By binding to a receptor and triggering the signaling cascade.

How can chemicals inhibit a pathway?

By blocking the receptor or interfering with signaling components.

What are feedback mechanisms?

Processes that regulate a system by increasing or decreasing its activity.

How does negative feedback maintain homeostasis?

It reduces a response when conditions return to normal.

How does positive feedback affect homeostasis?

It amplifies a response, moving conditions away from normal.