The proteins encoded by the genes cryIAc and cryIIAb control the __________.
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → Cotton bollworms
Bt toxin is a protein made by the bacterium Bacillus thuringiensis. It kills certain insects. The toxin is coded by genes called cry genes, and each cry gene works against a particular group of pests. The proteins of cryIAc and cryIIAb control the cotton bollworms. The protein of cryIAb controls the corn borer. These genes have been put into cotton to make Bt cotton.
(1) Cotton bollworms — Correct. cryIAc and cryIIAb control cotton bollworms.
(2) Maize borer — Incorrect. The corn (maize) borer is controlled by the protein of a different gene, cryIAb.
(3) Tobacco budworm — Incorrect. The tobacco budworm is one of the lepidopteran pests killed by Bt toxin in general, but it is not the pest linked to these two genes.
(4) Armyworm — Incorrect. The armyworm is also a lepidopteran pest, but it is not the pest controlled by cryIAc and cryIIAb.
Note: A similar question was also asked in CUET (UG) 2022 on 30-08-2022 (Slot 2).
NCERT Extract:
Biotechnological Applications in Agriculture – …
