NEET Biology Digestion And Absorption Based Practice Questions & Answers with Viewers Discussion and Detailed Explanation

Answer: (c)

Retinol (vitamin A) and calciferol are fat soluble vitamins but the pellagra is not the deficient disease of calciferol. Vitamin A cannot be synthesized by mammals and other vertebrates and must be provided in the diet. Green plants contain precursors of the vitamin, notably carotenes, that are converted to vitamin A in the intestinal wall and liver. The aldehyde derivative of vitamin A, retinal, is a constituent of the visual pigment rhodopsin. Deficiency affects the eyes, causing night blindness, xerophthalmia (dryness and thickening of the cornea), and eventually total blindness.

Pellagra is caused by the deficiency of vitamin $B_3$ or nicotinic acid or niacin.

Cobalamine and ascorbic acid (vitamin C) are water soluble vitamins. They are generally found together in the same foods with the exception of $B_12$ (cobalamine). The deficient disorders related to cobalamine, vitamin C and calciferol are –

Cobalamine – Pernicious anaemia

Ascorbic acid (vitamin C) – Scurvy

Calciferol (vitamin D) – Rickets (in children) and osteomalacia in adults.

Beri-beri is caused by the deficiency of vitamin $B_1$ (Thiamine).