What is meant by a signal cascade?

A signal cascade, also known as a signaling cascade, refers to a series of biochemical events in which a signal or stimulus triggers a sequence of reactions within a cell. This process typically involves the activation of proteins and enzymes through phosphorylation or other modifications, leading to a specific cellular response. Signal cascades are essential for various cellular functions, including growth, differentiation, and response to environmental changes. They amplify the initial signal, allowing for a robust response to external stimuli.