MPSC 2023 Prelims Paper-I · Question 42 of 100

Correct — option (2), which pairs a. with iv., b. with i., c. with ii. and d. with iii. Before matching anything, note that the two lists are printed side by side only because the reader has to join them; the order in which they happen to sit on the page asserts nothing. Take the vitamins one at a time. Statement a., Vit. A, pairs with iv., Night blindness. Vitamin A, or retinol, is the raw material from which the rod cells of the retina build rhodopsin, the pigment that lets the eye register very dim light. When the vitamin is short the rods cannot regenerate the pigment fast enough and the first symptom is an inability to see after dusk or on moving from a lit room into a dark one; if the deficiency deepens it goes on to dry the conjunctiva and cornea, the condition called xerophthalmia, and can end in blindness. Statement b., Vit. D, pairs with i., Rickets. Vitamin D governs the absorption of calcium and phosphate from the intestine, so without it the growing skeleton cannot be properly mineralised: in children the soft bones bend under the body's weight, giving the bowed legs and deformed rib cage of rickets, while the same deficiency in an adult, whose bones have stopped growing, produces osteomalacia instead. Statement c., Vit. C, pairs with ii., Scurvy. Ascorbic acid is required to build normal collagen, the protein that gives connective tissue, blood vessel walls and gums their strength, so a deficiency shows up as bleeding and spongy gums, loose teeth, bleeding under the skin and wounds that will not heal — the classic disease of long sea voyages. Statement d., Vit. B12, pairs with iii., Anaemia. Cobalamin, the only vitamin that contains a metal atom, cobalt, is needed for the DNA synthesis that lets bone marrow turn out red blood cells; without it the marrow releases large, immature and inefficient cells and the result is a megaloblastic anaemia. Only option (2) reproduces all four of these pairings.

• (1)(a) - (iii), (b) - (ii), (c) - (iv), (d) - (i) — Every one of the four pairings in this option is wrong, which makes it useful mainly as a check on whether the candidate can settle even one pair with confidence. It hands Vitamin A the anaemia that belongs to B12, gives Vitamin D the scurvy that belongs to C, attaches night blindness to Vitamin C, and leaves rickets with Vitamin B12. A single secure pairing is enough to strike it out: anyone who knows that Vitamin A protects night vision, or that Vitamin D and rickets go together through calcium and the growing skeleton, can eliminate this option after reading only its first or second entry, which is how matching questions should be worked.
• (3)(a) - (i), (b) - (iv), (c) - (iii), (d) - (ii) — This option swaps the first two vitamins and then swaps the last two, so it is built out of the two most tempting confusions at once. It gives rickets to Vitamin A and night blindness to Vitamin D, when the direction runs the other way: the retina depends on retinol and the skeleton depends on calciferol. It then gives anaemia to Vitamin C and scurvy to Vitamin B12, reversing the other pair as well. The mnemonic anchors that break both swaps are that the name retinol carries the retina inside it, and that scurvy is the disease of sailors deprived of fresh fruit, which is a Vitamin C story and could not be a B12 story since B12 comes from animal foods rather than from citrus.
• (4)(a) - (ii), (b) - (iii), (c) - (iv), (d) - (i) — This option gets none of the four right either, but it is the more dangerous of the fully wrong choices because it contains a half-truth about Vitamin C: it does not pair C with scurvy, yet it places scurvy at the top of the list against Vitamin A, close enough to catch a candidate who is scanning for the word scurvy rather than tracking which label it sits against. The disciplined method for a matching item is to write out your own four pairs before looking at any option, then find the option that reproduces your list exactly, because reading the options first invites you to search for a fragment you recognise instead of a set you have verified.

Vitamins are organic compounds the body needs in small quantities but cannot synthesise in sufficient amounts, so they have to come from the diet, and each deficiency disease is simply the failure of the particular job that vitamin performs. They divide into two groups whose behaviour differs in ways worth knowing. The fat-soluble vitamins A, D, E and K dissolve in fats, are absorbed along with dietary fat, and are stored in the liver and fatty tissue, so a deficiency takes a long time to appear and an excess can accumulate to toxic levels. The water-soluble vitamins — the B complex and vitamin C — are not stored to any great extent and any surplus is excreted, so they need regular replenishment and deficiency shows up sooner. Vitamin D is unusual in that the skin manufactures it from a cholesterol derivative under ultraviolet light, which is why sunlight rather than food is its principal source. Vitamin B12 is unusual in a different way: it contains cobalt, occurs essentially only in animal-derived foods, and needs a stomach protein called intrinsic factor to be absorbed, so a failure of that protein produces the same anaemia as a dietary shortage.

Vitamins and their deficiency diseases are among the most reliably repeated topics in MPSC's science section, and the Commission asks them in the matching format because that format punishes half-knowledge in a way a single-pair question does not. A candidate who is sure of three pairs still gets nothing unless the fourth falls into place. The working method that pays is to build your own answer before you read the options: cover the four printed choices, write down the pairing you believe in, and only then look for the option that matches it. The second habit is to remember that adjacency on the page means nothing. Here the printed layout puts Vit. A opposite Rickets and Vit. B12 opposite Night blindness, and neither pairing is right; the columns are set side by side because the reader has to join them, not because the printer has already done it. Note also that scientific names and abbreviations such as 'Vit. B12' are printed identically in both language columns, so a Marathi-medium candidate reads exactly the same four items.

• Vitamin A, retinol, is needed by the rod cells of the retina to make the pigment rhodopsin; deficiency causes night blindness first and, if it continues, the drying of the eye known as xerophthalmia and eventual blindness.
• Vitamin D, calciferol, controls the absorption of calcium and phosphate from the intestine; deficiency causes rickets with bent bones in growing children and osteomalacia, a softening of already formed bone, in adults.
• Vitamin C, ascorbic acid, is required for the synthesis of normal collagen; deficiency causes scurvy, whose signs are bleeding and spongy gums, loosened teeth, bleeding under the skin and wounds that do not heal.
• Vitamin B12, cobalamin, is the only vitamin containing a metal atom, cobalt, and is needed for the DNA synthesis behind red blood cell formation; deficiency produces a megaloblastic or pernicious anaemia.
• Vitamins A, D, E and K are fat-soluble and are stored in the liver, so deficiency appears slowly and excess can be toxic; the B complex and vitamin C are water-soluble, are not stored in quantity and must be supplied regularly.

• Treating the side-by-side printing of the two columns as an answer; here the printed adjacency pairs Vit. A with Rickets, which is wrong
• Swapping Vitamin A and Vitamin D, and so attaching rickets to the eye vitamin and night blindness to the bone vitamin
• Attaching scurvy to a B vitamin because it is remembered as a general dietary disease of sailors rather than specifically as a Vitamin C deficiency
• Assuming all anaemia is iron deficiency and so refusing to pair anaemia with Vitamin B12, which causes a distinct megaloblastic anaemia

MPSC's vitamin questions come in three recognisable shapes: a matching item like this one that joins four vitamins to four diseases, a single-pair question asking which vitamin prevents a named disease, and a chemical-name question asking for the scientific name of a vitamin or the disease caused by its absence. A fourth variant asks which vitamin is synthesised in the body rather than obtained from food, where the expected answers are Vitamin D from sunlight and Vitamin K from intestinal bacteria. Because the same four or five vitamins circulate through all these formats, the efficient preparation is a single compact table holding vitamin, chemical name, main sources and deficiency disease, learnt so that any one column can be produced from any other.

No directly related past PYQ was found.

• practice — not a real PYQ

  The deficiency of which of the following vitamins causes rickets in growing children and osteomalacia in adults ?

  • (a)Vitamin A
  • (b)Vitamin C
  • (c)Vitamin D
  • (d)Vitamin B12

  Answer(c) Vitamin D — it governs the absorption of calcium and phosphate from the intestine, so a shortage leaves bone poorly mineralised. In children whose skeleton is still growing this produces the bent limbs and deformities of rickets, while in adults, whose bones have stopped growing, the same deficiency softens already formed bone and is called osteomalacia.

• practice — not a real PYQ

  Which of the following vitamins contains the metal cobalt in its molecule and is required for the formation of red blood cells ?

  • (a)Vitamin C
  • (b)Vitamin B12
  • (c)Vitamin K
  • (d)Vitamin E

  Answer(b) Vitamin B12 — cobalamin is the only vitamin whose molecule contains a metal atom, cobalt, and it is needed for the DNA synthesis that allows the bone marrow to produce mature red blood cells. Its absence yields a megaloblastic anaemia in which the marrow releases large, immature cells, and because the vitamin needs intrinsic factor from the stomach to be absorbed, the anaemia can arise even when the diet supplies enough.