Homeostasis is defined as maintaining a constant internal environment. These conditions include water content, ion content, body temperature and blood glucose concentration. The brain is the centre that monitors and controls the body temperature. The blood glucose concentration is concentrated by the pancreas, which produces a hormone known as the insulin; this hormone is able to reduce the blood glucose levels. If there is not enough produced then the disease diabetes is developed.
Negative feedback mechanisms:
‘a body system that monitors a system output, that shuts off once an optimum output level is achieved and turns on if the output level dropped below optimum’ (reference: Walsh, 2010)For example if the body temperature is too hot then it will cool down, and if the body temperature is too cold then it would warm up. An example is ‘Hormone levels decrease so the body stimulates the organ to produce more. At a certain level, the body recognizes that there is too much and pulls back production (the negative feedback).’ (reference: http://answers.yahoo.com/question/index?qid=20090420140027AArF0f3) the brain and nervous system are very important in the process in homeostasis mechanisms . if a person has not eaten for 7 hours they will start to feel cold and tired, the nervous system and brain will detect this and after a warm meal, it will give you energy. There are many negative feedback systems which require: ‘receptors to detect change, a control centre to receive the information and process the response and effectors to reverse the change and re-establish the original state’ (Reference: Albworth et al, 2010).
Describe the mechanisms of temperature control:
All enzymes work best at the body temperature which is around 37 degrees. If the body temperature increases or decrease enzymes will not work properly or may even denature. In the brain there is a “thermoregulatory” will acts like the body’s thermometer, so if the body temperature is too high it will send messages around the body to decrease the temperature. When the body temperature is below the average temperature which is 37.5 degrees- so when someone is feeling cold, the body will have to try and maintain the body temperature and try and bring the temperature up. First there will be a drop in the temperature which will be detected by the hypothalamus. The brain will then send signals all around the body to start shivering. When the body starting shivering, this is a automatic muscle contraction. As this needs respiration, it releases some energy as heat. After minutes of shivering the body temperature should return to normal. The hairs around the body such as on the arms and legs will stick up, this will trap an insulating layer of air, which will keep the body warm. The blood vessels that are supplying skin capillaries will constrict this is to close off the skins bloody supply, the body wants to loose as least as possible. Another way the body can bring up the body temperature is to increase the metabolic rate. Lastly there will be no sweat produced. When the body temperature is above the average, this is when a person is feeling too hot. The body will need to maintain the temperature by doing may thing. The body will start to produce sweat via the sweat glands which are all around the body. The sweat is evaporated from the skin, which removes excess heat. The blood vessels supplying the skin will widen this is so more blood can flow, this means more heat will be lost to then surrounding environment. As the body is too hot, the metabolic rate will decrease in order to decrease the body temperature. Finally hairs on the body will lay flat close to the skin.
Mechanisms for regulation of blood glucose levels:
We have learned carbohydrates are broken down by enzymes, enzymes know as the digestive enzymes. When it carbohydrates are broken down it is changed into simple soluble sugars. When a person has a...
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