What is Vasoconstriction?
When we are too cold, blood vessels in the skin start to constrict. This reduces the flow of blood near the surface of the skin which also reduces heat loss which keeps us warmer.
What is Negative Feedback?
Negative Feedback ensures that in any control system, changes are reversed and changed back to the set level. E.g. it keeps our body temperature at a constant 37 degreees celcius.
Vasoconstriction and Vasodilation
What is Homeostasis?
The maintenance of a constant internal environment.
What is Vasodilation?
When we are too hot blood vessels in the skin start to vasodilate, this allows warm blood to flow to the surface of the skin where heat can be lost to the air and the environement around us making us cooler
What is the Hypothalamus?
It is the processing centre of the brain that controls body temperature. it does this by triggereing changes to effectors such as sweat glands and muscles controlling body hair.
The hairs on your skin can also help to control your body temperatre. They do this by lying flat when we are warm and rising when we are cold. The hairs trap a layer of air above the skin which helps to insulate the skin against heat loss.
Hairs lie flat when we are hot and stand upright when we are cold
Type 1 Diabetes
Caused by a lack of insulin
Can be controlled by:
- Monitoring the diet
- Injecting insulin
People have to monitor their blood sugar levels throughout the day. Their levels of physical activity and diet affects the amount of insulin they need.
This type of diabetes is inherited.
Type 2 Diabetes
Caused by a person's body being resistant to insulin.
Can be controlled by:
Type 2 diabetes is self inflicted. There is a link between obesity levels and the amount of people with type 2 diabtetes. In extreme cases people with type 2 diabetes would inject insulin into themselves, however other than that they would exercise regularly and have a controlled diet in order to maintain their blood glucose levels.
Diabetes is a condition where the blood glucose levels are too high in a persons body. it can be treated by injecting insulin into themsleves. This causes the liver to convert glucose into glycogen which reduces the blood glucose lebel and keeps it steady.