Water in the Body
Water makes up 70-75% of the body weight of the average human being. A person can survive for up to 4 weeks without food but no longer than 3 days without water. Water performs many different functions inside the body. It forms the bulk of blood and tissue fluid and is therfore essential for tansporting nutrients, hormones and wasteproducts around the body. Water helps control the delicate balances of concentrations within the cells.
This is the process by which water moves through permeables membranes. Water moves from an area of high/low water potential to one of low/high water potential until a dynamic equilibrium is reached.
Specific heat capacity, is a measurement of how much energy is required to cause an increase in temperature. For water this value is quite large, which makes it useful as a coolant in many different situations, including nuclear reactors. It is also an important property for the body as it is necessary to keep the tempeature quite constant so that enzymes, proteins which catalyse reactions vital to your bodies functioning, remain at the optimum temperature to work effectivly. Because such a large proportion of our body is made from water, it means lots of energy is required to make even small changes to our bodies temperature one of the reasons why it is so critical to life.