Cyclic Adenosine Monophosphate, or cAMP, is a molecule that plays a crucial role in cellular signaling. It is derived from adenosine triphosphate (ATP) and acts as a secondary messenger in various biological processes. cAMP helps transmit signals from hormones and neurotransmitters, influencing activities such as metabolism, gene expression, and cell growth. In cells, cAMP is produced by the enzyme adenylate cyclase in response to external signals. Once formed, it activates protein kinase A (PKA), which then phosphorylates target proteins to elicit specific cellular responses. This signaling pathway is vital for maintaining homeostasis and regulating numerous physiological functions.