Read the following passage carefully and answer the given questions.
Insulin consists of two short polypeptide chains- chain A and chain B, that are linked together by disulphide bridges. Some strains of Bacillus thuringiensis produce proteins that kill certain insects such as lepidopterans, coleopterans and dipterans. Bt toxin protein is converted into an active form of toxin due to the alkaline pH of the gut which solubilise the crystals. Transgenic animals that produce useful biological products can be created by the introduction of the portion of DNA (or genes) which codes for a particular product such as human protein (α-1-antitrypsin) used to treat emphysema. Plants, bacteria, fungi and animals whose genes have been altered by manipulation are called Genetically Modified Organisms (GMO). GM plants have been useful in many ways. Genetic modification has: (i) made crops more tolerant to abiotic stresses. (ii) reduced reliance on chemical pesticides (pest-resistant crops). (iii) helped to reduce post harvest losses. (iv) increased efficiency of mineral usage by plants (this prevents early exhaustion of fertility of soil). (v) enhanced nutritional value of food.
Identify the incorrect fact about genetic modification.
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → It has helped to increase post harvest losses.
Plants, bacteria, fungi and animals whose genes have been altered by manipulation are called Genetically Modified Organisms (GMO). The passage lists how GM plants have helped: more tolerance to abiotic stresses, less reliance on chemical pesticides, reduced post harvest losses, better use of minerals, and higher nutritional value of food.
Option (1) It has made crops more tolerant to abiotic stresses (cold, drought, salt, heat). — A correct fact. GM crops survive non-living stresses such as cold, drought, salt and heat better.
Option (2) It has reduced reliance on chemical pesticides (pest-resistant crops). — A correct fact. Pest-resistant crops such as Bt cotton protect themselves, so less pesticide is sprayed.
Option (3) It has enhanced nutritional value of food, e.g., golden rice, i.e., Vitamin ‘A’ enriched rice. — A correct fact. Golden rice is rice enriched with vitamin A.
Option (4) It has helped to increase post harvest losses. — An incorrect fact. Genetic modification has helped to reduce post harvest losses, not increase them. NTA changed one word of the book’s line, “reduce” to “increase”, and a true fact became false. Read every word before you mark the answer.
Note: The passage is taken from NCERT. NTA has put lines of the NCERT text together to make it. Most CUET (UG) questions come straight from NCERT, so study the book line by line, including figures and their titles.