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Homeostasis is the maintenance of a constant internal environment (in response to internal or external changes in the environment)Homeostasis can be maintained by negative feedback mechanisms which detect...

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The reflex arc is a series of events connecting a stimulus to a response. The stimulus, for example a hand touching a hot pan, stimulates the receptor...

Bile is a substance synthesised in the liver and released by the gall bladder. It is released into the small intestine and helps breakdown large fat droplets into smaller ones, via emulsification. This in...

via diffusion down a concentration gradient as O2 levels are higher in the lungs than in the blood. for faster diffusion you need:a large surface area (lungs have million of alveoli which are air filled s...