Bio chemistry... Help with my home work?

Water dissociates, therefore it acts as a good solvent to dissolve lots of ionic compounds. Helps to get transport or rid of excess ions in the body.

Water has a rather high heat capacity. Helps to maintain the temperature on earth.

1) Water needs a large amount of nergy to change from a liquid to a gas. This means that sweating can be a very efficient way of losing heat.

2) Water is a solvent for many different substances e.g. 1)ions such as Na+ and K+ 2) polar substances such as glucose and fructose 3) amino acids.

3) Actually water is a bad pH buffer, but it can dissolve substances that are good buffers. This is relevant to blood pH.

4) When water reaches about 4 degrees centigrade, it is at its most dense and sinks. At zero degrees water forms ice, which is less dense than water. This is an unusual property and it gurantees that ice floats. Result: ice does not collect and build up on the bottom of many lakes.

A buffer is something that reacts with an acid in teh body to balnce out acid base raections. So what they are saying is that the water reacts with volative substances in the body that would otherwise do damage by breaking down cell membranes and thinsg of that nature.

Water is also part of osmosis which is when water travels to a higher concebtrated area, maintaining equilibrium. This is how a cell keeps from bursting. When too much watyer is in a cell it goes outside teh cell due to osmosis instead of taking on even more water and bursting.

Hope this helps.