Diabetes is a disease where the concentration of glucose in the blood is not controlled properly by the body. In type 1 diabetes, the pancreas does not produce enough insulin. This can lead to high levels of glucose in the blood, which can be fatal.
Banting and Best
You should be able to evaluate experimental data from Banting and Best’s experiments which led to insulin being discovered.
Two doctors, Frederick Banting and Charles Best, made an extract from the pancreas in 1921. The extract had anti-diabetic properties, and they tested it successfully on diabetic dogs. The first tests in humans were carried out in 1922, and were a success too. Some patients who were in a diabetic coma even recovered. The extract contained the hormone insulin.
There are two types of treatment for diabetes:
Careful monitoring of food intake, with particular care taken over carbohydrates – which are digested into glucose.
Injecting insulin into the blood before meals. The extra insulin causes glucose to be taken up by the liver and other tissues. Cells get the glucose they need for respiration, and the blood glucose concentration stays normal.
Human enzymes work best at 37ºC, so the body’s temperature is controlled. A part of the brain called the thermoregulatory centre monitors and controls body temperature. It gathers information as nerve impulses from temperature receptors in:
Diabetes Diabetes, Diabetes Mellitus, is a chronic illness this means that it has no cure and the symptoms persist over a long period of time. This illness is a result of an imbalance of hormones, insulin, produced in the pancreas. Insulin plays an important role in how the body uses food. Insulin enables the cells in the bloodstream to absorb and use glucose for fuel. If the pancreas produces too ...
the brain – these are sensitive to the temperature of the blood flowing there
the skin – these are sensitive to skin temperature
Sweating is one way to help cool the body. We sweat more in hot conditions, so more water is lost from the body. This water must be replaced through food or drink to maintain the balance of water in the body.
Ions such as sodium ions and chloride ions are also lost when we sweat. They must be replaced through food and drink. If the body’s ion content is wrong, cells can be damaged.
Temperature regulation – higher
If you become too hot or too cold, there are several ways in which your temperature can be controlled. They involve sweating, shivering, skin capillaries and hairs.
When we get too hot:
Sweat glands in the skin release more sweat. This evaporates, removing heat energy from the skin.
Blood vessels leading to the skin capillaries become wider
they dilate – allowing more blood to flow through the skin, and more heat to be lost.
When we get too cold:
Muscles contract rapidly – we shiver. These contractions need energy from respiration, and some of this is released as heat.
Blood vessels leading to the skin capillaries become narrower
they constrict – letting less blood flow through the skin and conserving heat in the body.
The hairs on the skin also help to control body temperature. They lie flat when we are warm, and rise when we are cold. The hairs trap a layer of air above the skin, which helps to insulate the skin against heat loss.
Remember: Capillaries do not move up and down inside the skin. Temperature is regulated by controlling the amount of blood which flows through the capillaries.
Concepts of Lifetime Fitness September 1, 1997 Homeostasis is the state of equilibrium in which the internal environment of the human body remains relatively constant. Two excellent examples of homeostasis are how the body maintains a constant temperature and blood pressure during strenuous physical activity or exercise. Although there are many other activities in the body that display ...
HAIRS LIE FLAT
LOTS OF SWEAT IS PRODUCED – WHEN IT EVAPORATES, IT TRANSFERS HEAT TO THE ENVIRONMENT, COOLING YOU DOWN.
BLOOD VESSELS CLOSE TO TEH SURFACE OF TEH SKIN WIDEN – THIS ALLOWS MORE BLOOD TO FLOW NEAR THE SURFACE, SO IT CAN RADIATE MORE HEAT TO TEH SURROUNDINGS – THIS IS *VASODILATION.
**iF* YOU’RE EXPOSED TO HIGH TEMPERATURES YOU GET DEHYDRATED AND YOU CAN GET HEAT STROKE – THIS CAN KILL YOU