Physiology is the study of the mechanical, physical, and biochemical functions of living organisms.
Physiology has traditionally been divided into plant physiology and animal physiology but the principles of physiology are universal, no matter what particular organism is being studied. For example, what is learnt about the physiology of yeastcell can also apply to human cells.
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.
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.
