Given below are two statements, one labelled as Assertion (A) and the other as Reason (R).
Assertion (A) : Most of the vitamins are not synthesised in human body.
Reason (R) : Human organs synthesise

Question

Given below are two statements, one labelled as Assertion (A) and the other as Reason (R).
Assertion (A) : Most of the vitamins are not synthesised in human body.
Reason (R) : Human organs synthesise only essential micronutrients.
Select the correct answer from the codes given below :
Codes :

UnlockIAS · Accepted Answer

Correct — C, (A) is true but (R) is false. The Assertion is true almost by definition: a vitamin is an organic micronutrient that the human body cannot manufacture in adequate amounts, so it has to be supplied by the diet. A handful of partial exceptions exist — vitamin D is made in the skin from a cholesterol derivative under ultraviolet light, some niacin can be built from the amino acid tryptophan, and gut bacteria produce vitamin K2 and biotin — but for the great majority of vitamins the body has no synthetic route at all. The Reason, however, is false, and it fails in the most instructive way possible: it inverts the meaning of the word 'essential'. In nutrition, a nutrient is called essential precisely because the body CANNOT synthesise it and must obtain it ready-made from food. So saying that human organs 'synthesise only essential micronutrients' states the exact opposite of the truth. Since (A) is true and (R) is false, the code is (c).

Why the other options are wrong — (a) Rejected because the Reason is not true. It claims the body synthesises the essential micronutrients — but 'essential' is the technical label for exactly those nutrients the body cannot make. A false Reason can never be the correct explanation of anything.  (b) Also requires the Reason to be true, and it is not. This option is the standard trap for students who sense that the two statements do not fit together but never test the Reason on its own merits.  (d) This reverses the truth values. The Assertion is the well-established one — most vitamins genuinely are not synthesised in the human body, which is why they must be eaten — while the Reason is the flawed statement.

Concept: Nutrition divides nutrients into essential and non-essential, and the dividing line is a chemical one: can human cells build the molecule from what is already available? If they cannot, the nutrient is essential and the diet must supply it — this covers the nine essential amino acids, the essential fatty acids (linoleic and alpha-linolenic acid), the minerals, and almost all the vitamins. If the body can build it, the nutrient is non-essential, even though it may be vital to life; cholesterol, most fatty acids and eleven of the amino acids fall here. Vitamins were named and hunted down in the early twentieth century precisely because they were traces of something in food that the body could not do without and could not make; Casimir Funk coined the word 'vitamine' in 1912.

State PCS 2019 Q87 — Science & Technology PYQ with Answer

State PCS 2019 Q87 — Science & Technology PYQ with Answer