The trigger for activation of toxin of Bacillus thuringiensis is (A) Acidic pH of stomach (B) High temperature (C) Alkaline pH of gut (D) Mechanical action in the insect gut.
Option C.Bt toxins are initially inactive protoxins but after ingestion by the insect, these inactive toxins become active due to the alkaline pH of the gut which solubilizes the crystals. Hence, a high pH value is required to make Bt toxins active.
