Physiology (/ˌfɪziˈɒlədʒi/; from Ancient Greek φύσις (physis), meaning "nature, origin", and -λογία (-logia), meaning "study of") is the scientific study of function in living systems.

A sub-discipline of biology, its focus is in how organisms, organ systems, organs, cells, and bio-molecules carry out the chemical or physical functions that exist in a living system.

A silhouette of a human body showing various internal systems. image: wikimedia

Given the size of the field it is divided into among others: 

  • human physiology, 
  • animal physiology, 
  • plant physiology, 
  • cellular physiology, 
  • microbial physiology (see microbial metabolism), 
  • bacterial physiology, 
  • viral physiology.

The highest honor awarded in physiology is the Nobel Prize in Physiology or Medicine, awarded since 1901 by the Royal Swedish Academy of Sciences.

Source: derived from


The term for a medical doctor, physician, comes from this terminology. Although the individual who studies basic forces, i.e. physics of nature is called physicist.