LIFE SCIENCE

Detailed explanation-1: -Second messengers are small molecules and ions that relay signals received by cell-surface receptors to effector proteins.

Detailed explanation-2: -What are second messengers? Signals received by receptors at the cell surface or, in some cases, within the cell are often relayed throughout the cell via generation of small, rapidly diffusing molecules referred to as second messengers.

Detailed explanation-3: -Second messengers convert and amplify extracellular signals by activating protein kinases that serve physiological roles or by acting on intracellular ligand-gated channels to alter the membrane potential. The degradation of these second messengers leads to signal termination.