. Enzymes and health of the organism . Vitamins are designated by alphabets A, B, C, D, etc. Some of them are further named as sub-groups e.g.
B , B , B , B , etc. Excess of vitamins is also harmful and vitamin pills should not be taken without the advice of doctor. The term “ Vitamine ” was coined from the word vital + amine since the earlier identified compounds had amino groups. Later work showed that most of them did not contain amino groups, so the letter ‘e’ was dropped and the term vitamin is used these days.
Vitamins are classified into two groups depending upon their solubility in water or fat. (i) Fat soluble vitamins : Vitamins which are soluble in fat and oils but insoluble in water are kept in this group. These are vitamins A, D, E and K. They are stored in liver and adipose (fat storing) tissues.
(ii) Water soluble vitamins : B group vitamins and vitamin C are soluble in water so they are grouped together. Water soluble vitamins must be supplied regularly in diet because they are readily excreted in urine and cannot be stored (except vitamin B ) in our body. Some important vitamins, their sources and diseases caused by their deficiency are listed in Table . .
. . Classification of Vitamins Fish liver oil, carrots, butter and milk Yeast, milk, green vegetables and cereals Milk, eggwhite, liver, kidney Yeast, milk, egg yolk, cereals and grams Meat, fish, egg and curd Citrus fruits, amla and green leafy vegetables Exposure to sunlight, fish and egg yolk X e r o p h t h a l m i a (hardening of cornea of eye) Night blindness Beri beri (loss of appe- tite, retarded growth) Cheilosis (fissuring at corners of mouth and lips), digestive disorders and burning sensation of the skin. Convulsions Pernicious anaemia (RBC deficient in haemoglobin) Scurvy (bleeding gums) Rickets (bone deformities in children) and osteo- malacia (soft bones and joint pain in adults) .
Vitamin A . Vitamin B (Thiamine) . Vitamin B (Riboflavin) . Vitamin B (Pyridoxine) .
Vitamin B . Vitamin C (Ascorbic acid) . Vitamin D Sl. Name of Sources Deficiency diseases No.
Vitamins Table . : Some important Vitamins, their Sources and their Deficiency Diseases . Vitamin E . Vitamin K Vegetable oils like wheat germ oil, sunflower oil, etc.
Green leafy vegetables Increased fragility of RBCs and muscular weakness Increased blood clotting time Every generation of each and every species resembles its ancestors in many ways. How are these characteristics transmitted from one generation to the next? It has been observed that nucleus of a living cell is responsible for this transmission of inherent characters, also called heredity . The particles in nucleus of the cell, responsible for heredity, are called chromosomes which are made up of proteins and another type of biomolecules called nucleic acids .
These are mainly of two types, the deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) . Since nucleic acids are long chain polymers of nucleotides , so they are also called polynucleotides.