Module 2 Lessons Water Terminology Intracellular Fluid Compartment The fluid located inside your cells Extracellular Fluid Compartment The fluid located outside your cells Interstitial Fluids Fluids located between cells Electrolytes Charged ions that conduct an electrical current in a solvent such as water Solvent A liquid that acts as a medium in which substances dissolve Water is considered the universal solvent Water Balance The state whereby an equal amount of water is lost and replenished daily in the body Insensible Water Loss The water that is lost from the body daily through routine respiration and evaporation off the skin Dehydration The state whereby there is too little water in the body due to too much water being lost too little being consumed or a combination of both Diuretics Substances such as alcohol and some medications that cause the body to lose water Osmosis The movement of a solvent such as water from an area of lower concentration of solutes across a membrane to an area of higher concentration of solutes Osmosis balances the concentration of solutes between the compartments Antidiuretic hormone ADH A hormone that directs the kidneys to concentrate and reduce the volume of urine produced in order to reduce water loss from the body Hyponatremia A condition of too little sodium in the blood Compartmentalization The water in the body must be controlled and one way to do this is to confine it in compartments Intracellular water or the water found within cells of the body accounts for more than 50 of the water in the body Potassium is found in intracellular water Extracellular water or water found outside the cells of the body holds the remaining water Sodium is found in extracellular water Both potassium and sodium work to move water in and out of the cell through a method you can think of as a pump system Extracellular water is divided into three subcompartments Intravascular or the water within the vascular system This subcompartment is the water in the blood vessels Extravascular or water outside the vascular system This subcompartment holds the water that surrounds the blood vessels Interstitial or water surrounding the cells and in between the cells About 80 of extracellular water is categorized as interstitial Exchanges Water moves from and through the compartments by means of various body exchanges For example when water enters or exits a cell it takes small molecules of nutrients with it water also helps move air to the blood plasma and exchanges the oxygen in for carbon dioxide out Using water as the exchange medium allows small molecules of nutrients to move throughout the body From blood plasma to the intracellular area water is the transport system for moving chemical supplies throughout the body Some of the specific exchanges that occur when water moves through the body are Alveolar Air lung Blood Plasma The oxygen in is exchanged for carbon dioxide out Blood Plasma Erythrocyte Fluid Oxygen moves in or out as well as carbon dioxide water and other small molecules such as chlorides and carbonates Blood Plasma Interstitial Fluid Water moves in and out along with inorganic ions and small organic molecules Interstitial Intracellular Gases and water are exchanged as well as small organic molecules When water flows throughout the body it takes nutrients and or other chemicals with it and works to facilitate the exchange of chemicals from one form to another and from one area of the body to another Functions of Water Providing the transport system to move nutrients and facilitate chemical exchanges is one of the important functions of water In addition water also keeps the body s bones healthy helps dissolve nutrients assists in bio chemical reactions and helps regulate body temperature Bone Integrity Bone is made of a protein matrix surrounded and hardened by calcium and phosphorus and hydrated and hardened with water Therefore the hardness of bone is due in part to water and water is an important contributor to the rigidity of the skeletal system Universal Solvent Water is a universal solvent most of the nutrients in the body are soluble in water and it is this solubility that allows nutrients to be transported around the body efficiently by water The one nutrient that is not water soluble i e the fat nutrient has to be processed differently by the body in order for it to work well and that is one of the reasons an overabundance of the fat nutrient can lead to health problems Bio chemical Reactions Water is a required reactant in many biochemical reactions if water is not present the reactions will not occur As you will recall in digestion water is required to break bonds and is important in providing the building blocks of nutrients to the body Water is also important as a lubricant in the body It helps to moisturize skin it also prevents heat damage to joints by helping to dissipate the energy or friction that results from the bones of the joints rubbing together Regulating Body Temperature The body perspires to cool down When water comes out of the skin and evaporates it takes heat with it It takes approximately 1g of water to remove 6 Kcal of body heat Sources of Water Knowing how important water is to the body how do you supply all of the water the body needs Obviously drinking water or fluids is certainly one answer However drinking fluids is only one way of supplying water The body also receives much of its water from food The following chart shows how much water is contained in some common foods Food Water 65 76 Meat Bana na Bread 36 86 Orang e Chee se In addition to consuming fluids and food the third source of water for the body is metabolic water This is the water that is produced by the body through the metabolism of sugars fats and proteins 40 The amount of metabolic water produced depends on the amount of nutrients burned For example burning 100 grams of carbohydrates produces 60 grams of metabolic water Burning 100 grams of fat produces 107 grams of metabolic water and burning 100 grams of protein produces 40 grams of metabolic water Water Balance For optimal health and well being the amount of water coming into and going out of the body must be in balance Lack of water is called dehydration Having too much water in the body is called edema Let s look at the condition of edema first Edema causes the tissues to become swollen You will recall that water acts as a transport system moving nutrients from one part of the body to another