Homeostasis in humans - Essay Example

Homeostasis includes control of blood water balance, sugar level, temperature and urea in the blood. Cells combine to form tissues which form organs. Fluids contained in the cells are referred to as intracellular fluid while the fluid surrounding the cells are extracellular fluids. Nutrients such as glucose, oxygen and water are supplied through the extracellular fluid. (Chiras, 2003) The main body organs that are used to maintain homeostasis include the brain which has different parts responsible for various body functions, the liver and the kidneys and the skin.

To achieve coordination, sensors in the various body organs send signals to the brain. Looking superficially at the functions of these organs as pertains to homeostasis, the brain has three main roles in homeostasis which are executed by the hypothalamus, the autonomous nervous system and the endocrine system which has the pituitary gland as the master gland which controls and oversees the working of all other hormone producing parts of the body. The negative feedback works to maintain an optimum value which represents a set point in homeostasis.

When a condition deviates, this corrective mechanism returns it to norm. In order for it to be functional the receptors detect the change while the effectors carry out the corrective measures. The brain is the control centre that coordinates this response. If the deviations are not corrected, further deviation occurs and this is referred to as positive feedback. For instance, glucose is transported to the blood. In case of rise in the blood sugar, for example after a meal, regulation would involve both the pancreas and the liver.

In the pancreas, there are Islets of Langerhans which are groups of a special cells that secrete more insulin and less glucagon. For a system to attain a sustainable system, both the negative and positive feedbacks should be present. The lungs homeostatic functions involve regulation of pH and gaseous exchange