The Importance of Water on Living Oranisms
Water has importance inside cells and externally. This may be because it has interesting chemical and physical properties; it can be found naturally in all three of its states. However its molecules are bonded together by hydrogen bonds, this raises its melting and boiling points, i.e. its boiling point would be –120 C rather than 100 C. Also because it contains slightly negatively charged oxygen atoms and slightly positively charged hydrogen atoms making it polar. Water has been called a universal solvent because of it polarity. This means it can easily ionise substances, many compounds, whether ionic, polar or covalent will dissolve in it, therefore more reactions take place while in solution with water. Often in organisms substances must be in solution and water is the solvent. Plants can only obtain mineral salts in solution and human digestion will only dissolve soluble foods, meaning large starch molecules must be broken down into soluble sugars. Also many organisms living in water spend most of their time underwater, yet they require oxygen to respire, and as water is such a good solvent the required oxygen gas is dissolved in the water.
It is also used on a much larger scale for transport. Blood is mostly water, and is used to transport food, hormones, waste products (ammonia and urea) and oxygen, similarly in plants, sap is used to transport food and other substances. These substances all easily dissolve in water and then can be transported, whether it be oxygen to tissues, or hormones to various organs. Water is also used during fertilization when sperm must reach the ovum, the sperm is transported in semen, which is mostly water. Water's unique role is due to its physical and chemical properties, they allow water to act as an excellent solvent because of its polarity, water is an excellent support mechanism because of its cohesive forces within molecules and being virtually incompressible, this also means water is a good protective fluid. Water is also important because of its abundance. Although, as all life evolved in water, but some organisms having moved onto land, they will all still rely on the conditions they found and used to their advantages in their original habitat. Due to water's viscosity it is a useful lubricant, as it reduces friction giving
Some topics in this essay:
Water Water,
water water,
solution water,
water organisms,
transport food,
plant cells,
water solvent,
solvent polarity,
waste products,
provides support,
water due,
Join now to see the rest of the essay!
Approximate Word count = 825
Approximate Pages = 3 (250 words per page double spaced)
|
Example Essays Home
