Description
Physiology is a sub-discipline of biology that studies the functions of living systems. It focuses on the ways that organisms, organ systems, organs, cells and biomolecules carry out the chemical and physical functions that are necessary to maintain life of the system in question. Major divisions of this field are human physiology, animal physiology, plant physiology, fungi physiology, protist physiology and bacterial physiology but it includes literally every living system that exists on earth.