Physiology

Physiology is a branch of biology that deals with the mechanical, physical, and biochemical functions of living organisms. Physiology has classically been divided into plant physiology and animal physiology.

The field of animal physiology extends the tools and methods of human physiology to non-human animal species. Plant physiology also borrows techniques from both fields. Its scope of subjects is at least as diverse as the tree of life itself. Due to this diversity of subjects, research in animal physiology tends to concentrate on understanding how physiological traits changed throughout the evolutionary history of animals.

Other major branches of scientific study that have grown out of physiology research include biochemistry, biophysics, biomechanics, and molecular biology.

History

Anatomist William Harvey described blood circulation in the 17th century, providing the beginning of experimental physiology.

Areas of physiology

Physiology has several independent subdivisions. Electrophysiology deals with the operation of nerves and muscles; neurophysiology concerns the physiology of brains and cell physiology addresses the functioning of individual cellss.

Physiology also has many related and allied fields: Ecophysiology tries to undertand how physiological traits affect the ecology of a given animal or plant and vice-versa. Genetics is not the only factor that affects the physiology of animals and plants. Environmental strains wreak havoc on eukaryotic organisms as well. For organisms that do not dwell in aquatic habitats, water must be stored within their cellular environments. In organisms such as these, dehydration becomes a major issue.

Dehydration in humans can occur during elevated physical activity. Within the field of exercise physiology, studies have been conducted that show the effects of dehydration on homeostasis.