The cells of the body are bathed in blood and tissue fluid. These body fluids form the internal environment of the body and this environment is extensively controlled to maintain the internal environment at a near constant state, despite great flucuations in the external environment.

Homeostasis is the control process that maintains the body’s internal environment at a relatively constant level or within very narrow limits.

Homeostasis Regulates:

a. Blood glucose levels.

b. Pulse rate.

c. Breathing rate.

d. Body temp.

e. Water content of blood.

Negative feedback controls homeostasis. Some activity alters a condition in the internal environment, triggering a response that reverses the altered condition and returns conditions to normal.

a. Increase in one factor causes a decrease in another.

b. Decrease in one factor causes an increase in another.

Organ systems that help maintain the internal environment include:

a. Endocrine System:

b. Nervous System:

c. Excretory System: