2011 GS Paper I, all questions

UPSC Prelims 2011 · GS Paper I

Question 91: Science and Technology

Regular intake of fresh fruits and vegetables is recommended in the diet since they are a good source of antioxidants. How do antioxidants help a person maintain health and promote longevity ?

aThey activate the enzymes necessary for vitamin synthesis in the body and help prevent vitamin deficiency
bThey prevent excessive oxidation of carbohydrates, fats and proteins in the body and help avoid unnecessary wastage of energy
cThey neutralize the free radicals produced in the body during metabolism
dThey activate certain genes in the cells of the body and help delay the ageing process

AnswerThe answer is (c).

During metabolism the body produces free radicals, unstable molecules with an unpaired electron that damage cells, proteins and DNA, and are linked with ageing, cancer and heart disease. Antioxidants such as vitamins C and E and the carotenoids in fresh fruits and vegetables neutralise free radicals. They do not make vitamins, stop the normal oxidation of food, or switch genes on.

Why each option is right or wrong
  • (a) Antioxidants do not activate enzymes for vitamin synthesis.
  • (b) Oxidation of food is how the body gets energy; antioxidants do not stop it.
  • (c) Right: they neutralise free radicals produced in metabolism.
  • (d) They do not activate genes that delay ageing.

Explanation: written by UPSC Grade, not by UPSC.

Practise this paper timedPrevious questionNext question

Source: UPSC, Civil Services (Preliminary) Examination 2011, General Studies Paper I, Series A. The paper on upsc.gov.in.