| (i) It is activated by alkaline pH of the gut of the insect pest ultimately killing it. |
| (ii) It binds with the epithelial cells of the midgut of the insect pest ultimately killing it. |
| (iii) It does not kill the carrier bacterium which is itself resistant to this toxin. |
A) (i) and (ii)
B) (i) and (iii)
C) (ii) and (iii)
D) (i), (ii) and (iii)
Correct Answer: A
Solution :
[a] Bacillus thuringiensis forms the protein crystals, which contains a toxic insecticidal protein. Bt toxins are initially inactive protoxins but after ingestion by the insects their inactive toxin becomes active due to the alkaline pH of the gut, which solubilizes the crystals. The activated toxin binds to the surface of the midgut, epithelial cells swelling and lysis, further leading to death of the insect.
You need to login to perform this action.
You will be redirected in
3 sec
