I think what victoria said is correct to some pretence. The homeostasis of water is controlled by the hypothalamus which is located at the back of you head (P.S if you feel behind your head you should feel a very hard and rouncd bone/bump just a bit above the spinal cord, that is where the hypothalamus is!)
I learnt about homeostasis on this website====> hope it helps you !
homeostasis is the balancing act of you internal environment. Different organs control different things. When your body is working together to make sure you can carry out necessary proccess' this is called homeostasis.
For water and ion loss homeostasis your kidneys will control the amount of water in you cells and the amount of salt and other ions. Your kidneys do this by controlling the concentration of your urine. You gain water and ions by eating and drinking and you loose it by sweat (and urine)
Hope this helps :)
Answered Wed 11th April, 2012 @ 15:42 by Victoria Edited by Victoria on Wed 11th April, 2012 @ 15:43