AP BIOLOGY

Detailed explanation-1: -When a hormone enters a cell and binds to its receptor, it causes the receptor to change shape, allowing the receptor-hormone complex to enter the nucleus (if it wasn’t there already) and regulate gene activity.

Detailed explanation-2: -When a ligand binds to a cell-surface receptor, the receptor’s intracellular domain (part inside the cell) changes in some way. Generally, it takes on a new shape, which may make it active as an enzyme or let it bind other molecules. The change in the receptor sets off a series of signaling events.

Detailed explanation-3: -When a ligand binds an ion channel receptor, a channel through the plasma membrane opens that allows specific ions to pass through. This process requires a specialized membrane-spanning region of the receptor.

Detailed explanation-4: -When a ligand (the paracrine factor) binds its receptor in the extracellular region, the ligand induces a conformational change in the receptor’s structure. This shape change is transmitted through the membrane and changes the shape of the cytoplasmic domains.

Detailed explanation-5: -Receptors are a special class of proteins that function by binding a specific ligand molecule. When a ligand binds to its receptor, the receptor can change conformation, transmitting a signal into the cell. In some cases the receptors will remain on the surface of the cell and the ligand will eventually diffuse away.