Signal transduction refers to the process by which cells receive external signals and convert them into specific biological responses within the cell. These external signals can include chemical substances, light, temperature, or mechanical stimuli. Signal transduction typically involves a series of molecular interactions and chemical reactions to regulate the physiological functions of the cell, maintaining the balance of life activities. Signal transduction plays a crucial role in organisms, regulating important physiological processes such as cell growth, differentiation, apoptosis, and metabolism. A deeper understanding of signal transduction helps uncover the mechanisms of disease development and provides new targets and strategies for disease treatment.