Definition of Physiology

Physiology: The study of how living organisms function including such processes as nutrition, movement, and reproduction.

The word "function" is important to the definition of physiology because physiology traditionally had to do with the function of living things while anatomy had to do with morphology, the shape and form, of things.

Human physiology today is a science of wide scope:

• Some physiological studies are concerned with processes that go on within cells such as phagocytosis, the process by which cells engulf and usually digest particles, bacteria and other microorganisms, and even harmful cells. The physiology of cells is called cell physiology.
• Other physiological studies deal with how tissues and organs work, how they are controlled and interact with other tissues and organs and how they are integrated within the individual.
• Yet other physiological studies deal with how we respond to our environment. For example, to extremes of temperature (in arctic conditions versus the desert), to changes in pressure (deep under the ocean versus weightless in space), etc.

Human physiological processes are the functions of living persons and their parts, and the physical and chemical factors and processes involved.

Source from http://www.medterms.com