The evolution of signaling molecules has made it possible for cells of multicellular organisms, such as humans, to communicate with one another in simple and complex ways. Signaling molecules may be used to transmit information between cells (extracellular or intercellular signaling), or they may be involved in signaling cascades inside cells (cytoplasmic or intracellular signaling). Test your basic knowledge of signaling molecules by taking this simple quiz.
(1) Nitric oxide (NO) is a:
(2) This enzyme is responsible for the biosynthesis of nitric oxide (NO):
(3) Nitric oxide (NO) causes smooth muscle cells to __________.
(4) Nitric oxide (NO) acting on vascular smooth muscle brings about __________.
(5) The signaling gas, nitric oxide (NO), exerts its action on target cells by binding to this receptor: