Multiple choice

Bt toxin gene has been cloned from the bacteria and expressed in plants to provide resistance to insects without the need for insecticides.

Crystals of Bt toxin produced by some bacteria are unable to kill the bacteria themselves because

  1. they are resistant to the toxin

  2. the toxin exists as toxoid

  3. the toxin exists as protoxins

  4. bacteria encloses the toxin in a special sac
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The Bt toxin exists as an inactive protoxin, which needs digestion by an insect to be effective. There are various Bt toxins and each of this is specific to certain target insects. Crop plants have nowadays engineered to contain and express the genes for Bt toxin, which they produce in its active form.

Keep practicing — related questions