Which of the following statements is/are correct?
I. The Bt toxin gene has been cloned from the bacteria.
II. Genetic engineering is only limited to animals and has not been successfully used on plants.
III. Strains of Bacillus thuringiensis are utilised in producing bioinsecticidal plants.
IV. Genetic modification has increased the nutritional value of the food.
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → I, III, and IV
Biotechnology has been used widely in agriculture. Plants, bacteria, fungi and animals whose genes have been changed are called genetically modified organisms (GMOs).
I. The Bt toxin gene has been cloned from the bacteria. — True. The gene for Bt toxin was taken from the bacterium Bacillus thuringiensis and cloned and expressed in plants such as cotton.
II. Genetic engineering is only limited to animals and has not been successfully used on plants. — False. Genetic engineering has been used widely in plants. Bt cotton, Bt corn and golden rice are genetically modified plants.
III. Strains of Bacillus thuringiensis are utilised in producing bioinsecticidal plants. — True. The toxin gene from this bacterium, put into crops, lets the plants kill insects on their own. The book says this in effect created a bio-pesticide.
IV. Genetic modification has increased the nutritional value of the food. — True. One benefit of GM crops is enhanced nutritional value, for example golden rice, which is rich in vitamin A.
NCERT Extract:
Biotechnological Applications in Agriculture – “… Genetic modification has: (i) made crops more tolerant to abiotic stresses (cold, drought, salt, heat). (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, e.g., golden rice, i.e., Vitamin ‘A’ enriched rice. … Bt toxin is produced by a bacterium called Bacillus thuringiensis (Bt for short). Bt toxin gene has been cloned from the bacteria and been expressed in plants to provide resistance to insects without the need for insecticides; in effect created a bio-pesticide.”