Homeostasis

Insulin decreases blood glucose concentration by promoting the uptake of glucose by cells, especially liver and muscle cells, where it is converted to glycogen for storage. This process helps to lower blood sugar levels after a meal.

Negative feedback involves a response that counteracts the initial stimulus to maintain a set point.

The liver stores glucose as glycogen when blood glucose levels are high (stimulated by insulin) and breaks down glycogen into glucose to release into the blood when levels are low (stimulated by glucagon).

Glucagon increases blood glucose concentration by stimulating the liver to break down glycogen into glucose and release it into the bloodstream. This occurs when blood glucose levels are too low.

Type 1 diabetes is treated with regular insulin injections or the use of an insulin pump to maintain blood glucose levels within a normal range. Careful monitoring of blood glucose is also essential.

Sweating releases sweat onto the skin surface. As the sweat evaporates, it absorbs heat from the body, cooling the skin and reducing body temperature. This is crucial during exercise or in hot environments.

Shivering involves rapid, involuntary muscle contractions, which generate heat and raise body temperature. This is a response to cold conditions, helping to restore the body's internal temperature.

Vasodilation is the widening of arterioles supplying skin surface capillaries, allowing more blood to flow near the skin's surface. This increases heat loss through radiation, cooling the body down when it's too hot.

Vasoconstriction is the narrowing of arterioles supplying skin surface capillaries, reducing blood flow near the skin's surface. This decreases heat loss through radiation, helping to conserve heat when it's cold.

The hypothalamus in the brain acts as the thermoregulatory center. It receives information about body temperature and initiates responses like shivering, sweating, vasodilation, and vasoconstriction to maintain a stable internal temperature.