Homeostasis (Essay Sample)

Homeostasis
Name
Institution
Homeostasis
Homeostasis is a physiological process that maintains internal body environment through physiological and behavioral means. The process entails both long-term and long-term adjustment of temperature, water consumption, and other internal factors. The mechanisms of maintaining internal viability and defense of physiological events are very essential for well being of the bodies of living organisms. Essentially, bodies of living organisms control factors such as temperature, pH, glucose, oxygen, sodium, and calcium. Thus, the body regulatory mechanism ensures that the aforementioned factors remain at optimum levels for proper functioning of body systems such as circulatory, gaseous exchange, and central nervous system. Chiras (2011) argues that the internal systems remain constant and stable despite all variations or changes in the external environment.
Two mechanisms of controlling internal environment of the body exist. The mechanisms comprise of the positive and negative feedback mechanism. Negative feedback mechanism causes the variable under control to change in the opposite direction to the initial change. The change enables the variable to return to its optimum level or set point. For instance, the skin increases or decreases in body temperatures. When temperature is very low, smooth muscles of blood vessel constrict in order to allow blood to flow deep under the skin to prevent heat loss to the surrounding. When temperatures are very high, smooth muscles of blood vessels dilate and increases blood flow to the skin surface (Chiras, 2011). The overall process allows the body to lose excess heat.
The positive control mechanism involves changes in internal body environment that trigger control systems to amplify the change. The mechanism is self-perpetuating, and occurs is a series of cascades. For instance, during childbirth, nerve impulses stimulate hypothalamus that produces oxytocin hormone. Oxytocin acts on smooth muscles in the uterus, and increases the rate of contraction. Increased contraction expels t...