Class 12th Biology 2017 Set3 Outside Delhi Board Paper Solution
Question 2
Bt -toxins are released as inactive crystals in the bacterial body. What happens to it in the cotton boll worm body that it kills the boll worm.
Answer
It is converted into an active protein (due to alkaline pH of the gut of the boll worm), the toxin binds to midgut cells / create pores / causes cell swelling and lysis that kills the boll worm.
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