The study of the functions and mechanisms of living organisms is known as physiology. This scientific field explores how different systems within organisms, such as the circulatory, respiratory, and nervous systems, work together to maintain homeostasis and enable survival. Physiologists investigate how cells function, how organs operate, and how various biological processes contribute to the health and functionality of an organism. This discipline is crucial for advancing our understanding of health, disease, and the biological basis of physical performance, ultimately guiding medicine and biological research.