Beginning of Essay
September 1, 1997 Homeostasis is the state of equilibrium in which the internal environment of the human body remains relatively constant.  Two excellent examples of homeostasis are how the body maintains a constant temperature and blood pressure during strenuous ....

Middle of Essay
.... as shivering.  The production of Adenosine Triphosphate or ATP in the mitochondria of the muscles produces heat.  If the body temperature does not rise immediately after this, then a second function begins. The brain will signal the blood vessels near the skin to constrict or narrow in diameter.  This occurs so the heat deep in the muscles is conserved.  Since the vessels are now smaller in diameter, less blood is needed to fill them.  Since less blood is needed through the vessels, the heart begins to slow.  If the body remains in this slowed state, hypothermia could result.  Hypothermia is the condition in which metabolic processes ....