Homeostasis is the process of keeping the cells in the human body stable despite constant change that takes place internally and externally. The majority of the internal bodily environment is made up of fluid that surrounds cells known as interstitial fluid. When an internal bodily change occurs, homeostasis is what keeps the interstitial fluid at the proper temperature and also makes sure the body has the proper nutrients and oxygen levels. Homeostasis is like a bouncer at a bar. It sees a change take place and it takes proper action to ensure the environment remains stable.

All bodily structures fall under control of homeostatic mechanisms. Homeostatic mechanisms are controlled by two systems, the nervous system and endocrine system. The nervous system regulates homeostatic mechanisms by releasing nerve impulses in order to neutralize whatever change occurred. The endocrine system regulates homeostatic mechanisms by releasing hormones into the blood. When bodily changes take place, the nervous system tends to react and correct change more rapidly than endocrine system. Feedback systems are what maintain homeostasis. Feedback systems are made up of three elements.

The three elements of a feedback system are receptors, the control center, and effectors. Feedback systems maintain homeostasis by monitoring a bodily condition, evaluating what needs to be changed, making the necessary changes, and then starting all over again. The different bodily conditions that are monitored and controlled are known as controlled conditions. Examples of controlled conditions include blood sugar levels, blood pressure, and bodily temperature. Anything from an outside environment that causes a change to a controlled condition is known as a stimulus.

A couple of examples of a stimulus are extreme cold or infection. If a person has high blood sugar, that person’s receptors will acknowledge the high glucose level as a stimulus and send chemical signals to the control center. Then, the control center will send chemical signals to the effectors which will create a change in that person’s insulin levels in order to stabilize the blood sugar. (Brinson) References Tortora, G. J. and Derrickson B. (2007). Introduction to the Human Body: The Essentials of Anatomy and Physiology (7th Ed. ). Hoboken, NJ: John Wiley & Sons, Inc.