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Biotechnology and its Applications — BIOLOGY STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceBIOLOGYBiotechnology and its Applications3 Marks
Question
Why do lepidoplerans die when they feed on Bt cotton plant? Explain how does it happen.
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Answer

Bt cotton contains inactive toxin protein/protoxin/insecticidal protein/crystal protein, once the insect ingest it the inactive protoxins are converted into active form due to alkaline pH in gut, which solubilise the crystals, activated toxins binds to surface of midgut (epithelial cells), create pores causes cell swelling, lysis eventually leading the death of the insect pest.

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