Water and the Body

Water and the Body

Lindsey Frazier

SCI 241

Water 1

Water is a vital part of our body’s needs. It is a well known fact that a person may survive for a few weeks without food, but only a few days without water! The average adults body is 60% water weight and infants is even more at 70%. It is recommended that an adult male should drink 3.7 liters of water a day and women should drink 2.7 liters!

So why is water so important to our bodies? Bones are 25% water and muscles are 75% water! Water is also in our tears which help to lubricate our eyes and wash away dirt, saliva helps us to eat and keeps our mouths from drying out, and water in the amniotic sac helps to protect the unborn. Chapter 9 says water is held in cells and other body compartments by proteins, sodium, potassium, chloride, and other small molecules that are dissolved by water. Water is stored as intracellular fluid which is inside the cell and outside the cells called extracellular fluid. The extracellular fluid accounts for 1/3 total body water which is blood.

Water also has many more chemical functions as well. There are many amino acids, minerals, and glucose needed by the body and helps them dissolve. Water also helps to maintain the appropriate level of acidity. Water in blood helps regulate body temperature because water holds heat and changes temperature slowly, keeping our temperatures constant. Water is able to do this because it releases or decreases the amount of heat lost at the surface of the body. Water also helps the body to sweat. This function is extremely important, when the body’s temperature rises, in order to maintain the normal temperature and not over heat, the brain sends a message to our sweat glands and a mixture of water and salt is released which allows for out body’s to keep cool.

Water 2

Our bodies require a healthy nervous system and our muscles to work properly. Our nerves are able to send and receive messages just like our muscles are able to contract because of electrically charged ions that we get from water. These are called electrolytes. There are three important electrolytes: sodium, potassium, and chloride.

The kidneys conserve sodium which provides a mechanism to conserve body water. This mechanism helps to regulate blood pressure. There is a chance of losing too much salt through sweating. If you exercise and lose more sodium than you intake the blood pressure drops. If this happens, the body sends a message to the kidney’s which release hormones. Kidneys release the enzyme rennin and the protein angiotensin II and both help to raise blood pressure back to its normal level. The body also has a way of adjusting if blood pressure rises too high.