AP BIOLOGY

Detailed explanation-1: -Second messengers are small intracellular molecules that mediate the effects of first messengers, i.e., neurotransmitters and hormones. Some of the important second messengers in the nervous system are cAMP, cyclic guanosine monophosphate (cGMP), diacylglycerol (DAG), inositol trisphosphate (IP3), and Ca2 + ions.

Detailed explanation-2: -Second messengers are generated within the cell as a downstream step in signal transduction cascades initiated by the interaction of an external stimulus with a cell surface receptor.

Detailed explanation-3: -They are one of the triggers of intracellular signal transduction cascades. Examples of second messenger molecules include cyclic AMP, cyclic GMP, inositol triphosphate, diacylglycerol, and calcium.