Physiology is the discipline of the normal function of living systems. Physiology deals with the processes and mechanisms that allow an organism to survive, grow, and develop. Physiological processes are the ways in which organ systems, organs, tissues, cells, and biomolecules work together to accomplish the complex goal of sustaining life.

Physiological Mechanism is the mechanism by which the organ systems of the body function. Physiological mechanisms comprise the smaller physical and chemical events that make up a larger physiological process. Human physiology studies the functions of humans, their organs and cells, and how all of these functions combine to make life, growth, and development possible.