Question

The Bt toxin is used for killing nematodes in crop plants. But, it is non-toxic to humans. Select the correct reason for this

• A. The pro Bt-toxin activation requires temperature above human body temperature
• B. The Bt-toxin recognises only insect-specific targets.
• C. The pro Bt-toxin activation requires pH lower than that present in the human stomach.
• D. Conversion of pro Bt-toxin to Bt-toxin takes place in highly alkaline conditions.

Answer 1

Answer: (D)

Conversion of pro Bt-toxin to Bt-toxin takes place in highly alkaline conditions.

Bt toxins are used to kill insects but for humans, it is non-toxic because it behaves as a dietary protein. These breakdown very rapidly due to high acidic conditions in the human stomach and are harmless. As human stomach digests the concerned protein hence, it is not toxic to humans.

So the correct option is 'Conversation of pro-Bt toxin takes place in highly alkaline solutions'.