Class 12 NEET Biology Biotechnology and Its Applications

Concept:$Bacillus\ thuringiensis$ (Bt) produces insect-specific toxin proteins coded by $cry$ genes, used in developing pest-resistant crops.Key Fact:$cryIAc$ gene controls cotton bollworms, while $cryIAb$ gene controls corn borer.Explanation:Bt toxin genes are selected based on the target pest and crop.The protein from $cryIAc$ specifically kills cotton bollworms.The protein from $cryIAb$ specifically kills corn borer.Therefore, the required combination is $cryIAc$ for cotton bollworm and $cryIAb$ for corn borer.Answer:Option A ($cryIAc$ and $cryIAb$).