NEETZoologyBiotechnology and Its Applications
Once the inactive Bt toxin is converted into its active form in the insect gut, what is the immediate sequence of events that leads to the death of the insect?
Options
- AThe active toxin binds to foregut epithelial cells causing severe dehydration and starvation.
- BThe active toxin binds to the surface of midgut epithelial cells and creates pores that cause cell swelling an
- CThe active toxin binds to midgut epithelial cells and competitively inhibits the release of essential digestiv
- DThe active toxin enters the nervous system and inhibits the release of neurotransmitters at the neuromuscular
Correct answer
B. The active toxin binds to the surface of midgut epithelial cells and creates pores that cause cell swelling an
Step-by-step solution
The Bt toxin is ingested by the insect as an inactive protoxin and is converted to its active form due to the alkaline pH of the insect gut. Once activated, the toxin binds specifically to the surface of the midgut epithelial cells. This binding creates pores in the cell membrane, which leads to cell swelling and lysis, eventually causing the death of the insect. The distractors are incorrect because the toxin targets the midgut rather than the foregut, and its cellular mechanism is pore formation leading to lysis,