Bio1 - Cell signaling and homeostasis

What is a Hormone?

A molecule that acts as a long distance signal between cells in the same multicellular organism

What is a ligand?

Any molecule that binds to a receptor and triggers a response.

A hormone is a type of ligand

What is signal transduction?

A change in the form a signal takes

What is a phosphorylation cascade? When does it happen?

A chain reaction that amplifies the signal from a chemical messenger

Occurs when kinase phosphorylates multiple target proteins, which then phosphorylate multiple target proteins

What is a second messenger?

An Ion or Small molecule that is released in response to a chemical messenger binding to a cell-surface receptor and acts as an intracellular signal

What is a set point?

The preferred value or range of a variable or condition for homeostasis

What is membrane voltage?

An electrical potential created by a separation of charges across a membrane

What form does electric current take in cells?

Ions

What directions do substances move on their electric potential gradient?

Down electrical gradient, toward unlike charges, away from like charges