NEET2026BiologyChapterActual
Which of the following statements is incorrect regarding the insect-resistant crops developed using Bacillus thuringiensis ?
Options
- AThe choice of specific cry genes for genetic modification depends on both the crop type and the targeted pest.
- BThe Bt toxin protein exists as an inactive protoxin in the bacterium and is solubilised by the alkaline pH of
- CThe activated toxin binds to the surface of midgut epithelial cells, creating pores that lead to cell swelling
- DThe proteins encoded by the genes cryIAc and cryIIAb are specifically used to control the corn borer.
Correct answer
D. The proteins encoded by the genes cryIAc and cryIIAb are specifically used to control the corn borer.
Step-by-step solution
The choice of specific cry genes depends on the crop and the targeted pest, as most Bt toxins are insect-group specific. The Bt toxin protein exists as inactive protoxins but once an insect ingests the inactive toxin, it is converted into an active form of toxin due to the alkaline pH of the gut which solubilise the crystals. The activated toxin binds to the surface of midgut epithelial cells and creates pores that cause cell swelling and lysis and eventually cause death of the insect. The proteins encoded by the g