One of the ways that cells communicate with each other is by secretion of various molecules. The secreted molecule is known as

A signaling molecule is the way by which cells communicate with each other. Three general types of intercellular communication are mediated by messengers in the ECF: neural -in which neurotransmitters are released at synaptic junctions endocrine - in which hormones and growth factors reach cells the circulating blood or the lymph paracrine -in which the products of cells diffuse in the ECF to affect neighboring cells that may be some distance away.