Vitamins

 name differnt vitamins ,

symptoms of difiency of vit D, Vit K 10mark

VITAMINS:- (2 mark)

Vitamins are defined as "Small organic molecules present in diet which are required in small amounts "

 • most of the vitamin are not synthesized in the body and hence they most be supplied in the diet.

 • however, few provitamins are present in the body , which are converted to vitamins.

types of vitamin:

Vitamins are divided into two groups

 1. Fat soluble vitamins

 • Vitamin A

 • Vitamin D

 • Vitamin E

 • Vitamin K

 2. Water soluble vitamins

 • Vitamin B complex

 • Vitamin C

Vitamin A (5 Mark)

 • They are retinol (vitamin A alcohol), Retinal (vitamin A aldehyde) and retinoic acid (Vitamin A acid).

 • in nature vitamin A occurs in two forms.

 a. retinolesters- in the food of animal origin.

 b. carotenes- in plant foods as provitamin.

 • in the intestine, pancreatic esterase hydrolyzes retinolesters present in the diet to retinol and free fatty acid in the presence of bile salts. Retinol is absorbed by mucosal cells.

Function of vitamin A

 • Retinal is required for normal and colour vision.

 • Retinol is required for reproduction and growth.

 • Retinoic acid is required for synthesis of glycoprotein are mucopolysaccharide.

 • Retinol is required for differentiation and function as a steroid hormone.

 • Retinoic acid also promote growth and differentiation and also act as a steroid hormone.

 • Retinol and Retinoic acid are involved in regulation of gene expression.

deficiency of vitamin A

 1. night blindness

 • loss of night vision is the major initial symptoms of vitamin A deficiency.

 2. growth of bone and formation of tooth are defective. Thick and long bones are formed.

 3. Nerve growth are also affected. Degeneration of myelin sheath occurs.

 4. Keratinisation of mucus secreting epithelial cells lining respiratory tract and reproductive tract occurs. Thus mucus secretion by salivary gland and lacrimal gland is also affected.

 5. deposition of carotene in skin (xeroderma) gives rise to characteristic toad skin appearance.

 6. reproductive disorders like testicular degeneration, resorption of foetus or foetal malformation are absorbed.

 7. degenerative changes in kidneys.

sources:

 a. animal sources

 • liver of sheep or goat is excellent source.

 • marine fish oil, shark liver oil , butter , egg and milk a good source.

 b. plant sources

 • plant oil like red palm oil is excellent source.

 • leafy vegetables, coriander leaves, curry leaves spinach and cabbage are good sources

 • yellow pigment red fruits papaya mangoes jackfruit banana and Orange also contain vitamin A in good amount.

Vitamin D deficiency symptoms:

 1. Rickets

 • in children vitamin D deficiency causes rickets

 • It result in soft bone.

 • it leads to deformities in skull, chest ,spine ,legs and pelvis

 2. Osteomalacia

 • vitamin D deficiency causes osteomalacia in adults.

 • it is seen in pregnant women and women with inappropriate diet

 • skeletal pain is early sign.

 • deformities of spine and pelvis and legs are seen.

 3. Osteoporosis

 • vitamin D causes osteoporosis in old people

 • decrease in photolysis of provitamins with age and decrease sex hormone production may leads to vitamin D deficiency.

 • symptoms are bone pain and porous bone. Bone fractures are common.

vitamin K deficiency symptoms:

 1. hemorrhage

 • most common vitamin K deficiency symptom is hemorrhage in the newborn.

 • uncontroled bleeding through nose and gastrointestinal tract is likely to occur.

 • it can be treated successfully with intramuscular injection of vitamin K.

 2. in adult vitamin K deficiency really occur. however prolonged use of antibiotics may cause vitamin K deficiency due to elimination of intestinal flora.