Pulmonary hypertension is a rare lung disorder in which the arteries that carry blood from the heart to the lungs become narrowed, making it difficult for blood to flow through the vessels. As a result, the blood pressure in these arteries -- called pulmonary arteries -- rises far above normal levels.
Homeostatic Control Mechanisms Homeostatic Control Mechanisms are devices for maintaining or restoring homeostasis. They involve virtually all of the bodyâs organs and systems.
Almost all homeostatic control mechanisms are negative feedback mechanisms. These mechanisms change the variable back to its original state or âideal valueâ. A good example of a negative feedback mechanism is a home thermostat (heating system).The thermostat contains the receptor (thermometer) and control center.he control of blood sugar (glucose) by insulin is another good example of a negative feedback mechanism. When blood sugar rises, receptors in the body sense a change. In turn, the control center (pancreas) secretes insulin into the blood effectively lowering blood sugar levels.