Parts of a control systemSpec 4.5.1
All control systems include three types of component.
| Component | What it does | Examples |
|---|---|---|
| Receptors | Cells that detect stimuli (changes in the environment) | Temperature receptors in the skin |
| Coordination centres | Receive and process information from receptors | The brain, the spinal cord and the pancreas |
| Effectors | Muscles or glands that bring about responses which restore optimum levels | A muscle that contracts; a gland that secretes a hormone |
The sequence is: stimulus, receptor, coordination centre, effector, response. The response restores the optimum level, which the receptors then detect again.
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Define homeostasis.
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The regulation of the internal conditions of a cell or organism to maintain optimum conditions for function, in response to internal and external changes.
Name three things controlled by homeostasis in the human body.
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Blood glucose concentration, body temperature and water levels.
What do receptors do?
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They detect stimuli (changes in the environment).
Name the two types of effector.
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Muscles and glands.