Wednesday, September 7, 2011

Homeostasis


Homeostasis is the tendency of an organism or cell to regulate it's internal conditions, usually by a system of feedback controls, so as to stabilize health and functioning,regardless of the outside changing conditions.The liver,kidneys,and the brain help maintain homeostasis. The liver is in charge of metabolizing toxic things and maintaining carbohydrate metabolism.kidneys are in charge of regulating blood,maintenance of salt and ion levels in blood. Heat is mainly produced by the liver and muscle contractions. High temperatures can be stressful to some body's. Energy intake is internal heat produced plus external work plus steerage. Blood glucose is regulated with two hormones insulin and glucagon which is released from the pancreas. When blood sugar levels get too high, insulin is also released from the pancreas. Sugar is steered in the body as glucagon. When blood calcium gets too low, calcium sensing receptors in the parathyroid gland begin to work. It increases blood calcium and releases from bones. Decreasing calcium levels in the blood causes more calcium to be fixed in the bones. Positive feedback is how the body works really fast when your hot or cold like when your hot you sweat and when your cold you shiver. Negative feedback is how much pressure is on your body especially with temperature change.