• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Homeostasis what it is and why the body does it.

Extracts from this document...


Homeostasis what it is and why the body does it It is the process in which human body maintains a steady interior environment regardless of the exterior changes. The body organs can only maintain their functions powerfully within only a narrow range of conditions. For example body temperature, acidity, blood pressure, blood glucose levels, heart rate, respiratory rate and water balance. When a condition changes from where its original point is for working optimally. Its automatic regulatory mechanisms are set to work to work against the annoyance and to re-establish its original point. In order for homeostasis to occur regardless of which body system is involved receptors are needed to detect changes that are in the exterior environment. A control centre (mostly in the brain) to receive and to act on the information the receptors is giving. Effectors act to bring the system back to normal. This is called negative feedback. Negative feedback is the most common type of homeostatic control. Effecto Positive feedback effects are rare because they stimulate greater deviations from the normal and then result in a bust situation. ...read more.


More oxygen will be consumed as a result of more carbon dioxide and water waste manufacture. Homeostatic mechanisms involved in controlling heart rate When any form of excitement, fear, stress or exercise is taken out your brain acts as the control centre. It stimulates the release of adrenalin from the adrenal glands situated at the top of each kidney. It also sends impulses down the synaptic branch of the nervous system to the heart and other organs. These actions boot the heart making it beat harder and stronger. When the heart beats faster it sends more blood around the body. But the blood is distributed between organs and the muscles get the greater share. The skin and the digestive system receive small amounts of blood. This is the reason you will look pale and feel nauseous. This is called a primitive response that enables you to run away or stand and fight. Your blood pressure and breathing rate rise, secretions decrease making your mouth dry and it can be difficult to swallow. Adrenaline is destroyed once the emergency is over. ...read more.


Low oxygen and increased carbon dioxide concentrations- chemoreceptors can be triggered by high and low concentrations of chemicals, like oxygen carbon dioxide hydrogen ions and ph levels. Homeostatic mechanism involved in controlling temperature In your brain is there is an area called the hypothalamus. The hypothalamus has a thermo-regulatory centre and this detects the temperature of your blood. You also have thermo-receptors in your skin and these detect the temperature outside. You can increase your temperature by doing exercise, or putting on extra layers of clothing. You can decrease your temperature by removing clothes, lying in a cool place, etc. At extreme internal body temperatures your body has to employ other strategies. Muscles are also sent messages when you are cold. They make you shiver, warming you up. Your Low Critical Temperature is about 27� C and at temperatures this low your metabolic rate changes. At your Lower Lethal Temperature (about 25� C) your system will collapse and you will probably die. Your High Critical Temperature is very high, but if it is reached your metabolic rate cannot decrease to lower it. It increases out of control. If your Upper Lethal Temperature of about 42�C is reached you will die. Gifty ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Humans as Organisms section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Humans as Organisms essays

  1. Homeostatic mechanisms I have monitored.

    As the heart is worker faster and harder there is an increase in the blood pressure which can be measured. Pulse rate also increases as blood travels around the body faster. Possible Sources of Error When taking my measurements I must remember possible areas open to error such as reading

  2. human body system

    Veins take blood back to heart except in hepatic portal vein. They have thin walls and expand easily. Capillaries are single layer of cell. They go through organs and tissues and have once thick cells. Respiratory Respiration means to breathe in oxygen and to breathe out carbon dioxide.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work