Functions
Water in our bodies has many very important functions. Here are some of them:
- It is the solvent for all hydrophilic fluids in the body including: blood, lymph, the fluid around the brain and spinal cord, gastric juices, pancreatic juices and bile.
Blood is a water-based body fluid in the circulatory system of humans. It delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood is composed of blood cells suspended in blood plasma.
Lymph is a clear watery fluid that is collected from the tissues and returned to central circulation. Lymph flows a system of lymph vessels and intervening lymph nodes. This system is patrolled by immune cells that eliminate pathogens. Sometimes when we are ill lymph nodes grow and become painful.
Cerebrospinal fluid is a clear, colorless water-based body fluid found within the tissue that surrounds the brain and spinal cord. CSF is produced by specialized cells in the brain. CSF cushions the brain and spinal cord from sudden impact or injury. The fluid also washes the brain removing waste especially when we are asleep.
Gastric juice is a thin, clear, virtually colorless acidic fluid secreted by the stomach glands and active in promoting digestion. It contains water, mucus, hydrochloric acid, pepsin, and intrinsic factor.
Pancreatic juice is an alkaline liquid secreted by the pancreas, which contains a number of digestive enzymes, including trypsinogen, chymotrypsinogen, elastase, carboxypeptidase, pancreatic lipase, nucleases and amylase.Â
Bile is a bitter, alkaline, brownish-yellow or greenish-yellow fluid that is secreted by the liver, stored in the gallbladder, and discharged into the duodenum and aids in the emulsification, digestion, and absorption of fats.
Other important functions include:
- The production of urine which is important for water balance and elimination of nitrogen waste.
- Facilitating chemical reactions between nutrients and other substances.
- Facilitating conduction of electrical signals in nerves and muscles by allowing dissociation of minerals into charged particles (ions) and their flow across the cell membranes.
- Temperature regulation and waste elimination through sweating.
- Lubrication of joints.
- Moisturization of the skin, eyes and mucous membranes in the respiratory, gastrointestinal, urinary and genital tract.