By Water
The highest proportion of the body mass of living organisms is composed of water which is an inorganic compound. Two third (2/3rd) of the body weight of most of organisms is by water. Water is an essential medium for the maintenance of living matter. Life originated in water. Composition of water is simple. As water is the most abundant inorganic compound found in livings beings, it is important in many biological functions. The table below, shows the specific properties of water and contribution of them to the maintenance of life.
Minerals
Minerals are important as a nutrient constituent to maintain the life processes of organisms. They are absorbed as trace or macro elements into the body. The elements needed in higher amounts are known as macro elements and the elements needed in small amounts are known as trace elements.
7% of the body weight is by minerals. ¾ th of the above amount is by Calcium and Phosphorous. Other than that Potassium, Iron, Magnesium, Copper and Iodine are also included. when the elements are not present in correct amounts, plants and animals show deficiency symptoms.
Functions of minerals in plants and deficiency symptoms of them are mentioned in the following table.
Vitamins
They are organic compounds important in bio chemical reaction. Vitamins can be classified into 2 groups according to the solubility in water. Vitamin B and C are
water soluble and A, D, E, and K are insoluble in water. But these are fat soluble. The vitamins are needed for activities of human body, Their uses and deficiency symptoms are given in table
