NEETZoologyBiotechnology and Its Applications
How is the Bt toxin activated?
Options
- ABy the alkaline pH of the gut
- BBy the insect ingesting the inactive toxin
- CBy forming protein crystals
- DBy causing cell swelling and lysis
Correct answer
A. By the alkaline pH of the gut
Step-by-step solution
Bt Cotton: Some strains of Bacillus thuringiensis produce proteins that kill certain insects such as lepidopterans (tobacco budworm, armyworm), coleopterans (beetles) and dipterans (flies, mosquitoes). B. thuringiensis forms protein crystals during a particular phase of their growth. These crystals contain a toxic insecticidal protein. Why does this toxin not kill the Bacillus? Actually, the Bt toxin protein exist as inactive protoxins but once an insect ingest the inactive toxin, it is converted into an active for