Question

Crystals of Bt-toxin produced by some bacteria do not kill the bacteria themselves because

• A. Bacteria are resistant to the toxin
• B. Toxin is immature
• C. Toxin is inactive
• D. Bacteria encloses toxin in a special sac

Answer 1

The correct option is C Toxin is inactive

Cry proteins produced by some of the Bt strains do not kill the bacteria themselves because the toxin is inactive. In bacteria, the toxin is present in an inactive form, called as prototoxin, which gets converted into active form when it enters the body of an insect. It combines with the intestinal receptors of certain specific insects.

So, the correct answer is option C.