| A | B |
|---|
| signal transduction pathway | a mechanism linking a mechanical or chemical stmulus to a specific cellular response |
| local regulator | a chemical messenger that influences cells in the vicinity |
| hormone | chemical signals in multicellular organisms hat are made in special cells, carried by body fluid and used to alter the function of other specific cells |
| ligand | a molecule that binds specifically to a receptor sit of another molecule |
| G-protein-linked receptor | a signal receptor protein in the plasma membrane that responds to the binding signal mlecule by activating the G-protein |
| tyrosine kinase | an enzyme that catalyzes the transfer of phosphate groups from ATP to the amino acid tyrosine on a substrate prtein |
| ligand-gated ion channel | a protein pore in the plasma membrane that opens o closes in response to a chemical signal, allowing or blocking the flow of specific ions. |
| protein kinase | an enzyme that transfers a phosphate group from ATP to a protein |
| protein phosphatase | an enzyme that removes phosphate groups from proteins often functioning to reverse the effect of a protein kinase |
| second messenger | a small, nonprotein, water-soluble molecule or ion, such as calcium in or cyclic AMP, that relays a signal to a cell's interior in response to a signal received by a signal receptor protein |
| cyclic AMP | cyclic adenosine monophosphate, a ring-shaped molecule made frm ATP that is a common intracellular signaling molecule in eukaryotic cels. |
| adenyl cyclase | an enzyme that converts ATP to cyclic AMP in response to a chemical signal |
