Extracellular Fluid a. Interstitial Fluid b. Plasma B. Animal Diversity 1. Osmoregulators C. Acquatic Organisms 1. The regulatory systems of the animal body maintain a relatively stable internal environment through a process called . Some aquatic endotherms use countercurrent heat exchange to maintain a consistent internal temperature.
Extracellular fluid is composed of which bathes the cells, and the portion of the blood known as .
An organism whose body temperature is 37 degress centigrade when the environment is warm or cold is called . .