Animal Physiology

The maintenance of a relatively stable internal environment (temperature, pH, ion and fluid balance) despite changes in external conditions.

A regulatory loop in which a change triggers a response that counteracts it, returning the variable toward a set point (e.g., body temperature, blood glucose).

A loop that amplifies the original stimulus, driving the variable further from baseline; used in processes like childbirth and blood clotting.

Transports oxygen, nutrients, hormones, and wastes throughout the body via blood pumped by the heart through blood vessels.

Two atria (upper, receiving chambers) and two ventricles (lower, pumping chambers); the right side handles deoxygenated blood and the left side oxygenated blood.

Arteries carry blood away from the heart, veins return blood to the heart, and capillaries are thin-walled vessels where gas and nutrient exchange with tissues occurs.