Bacillus Thuringiensis (BT) is described as a toxin that does what?

• A. It is a broad-spectrum insecticide that affects many pests
• B. AKA BT; toxin that disrupts feeding patterns, starves insect (only works on some insect species)
• C. It is a fungicide
• D. It is a herbicide

Answer: (B)

Bt toxins are insecticidal proteins produced by Bacillus thuringiensis. When insects ingest them, the toxins are activated in the gut and damage the gut lining, which disrupts feeding and leads to death, often by starvation. A key point is that this effect is specific to certain insect groups, so it’s not a broad-spectrum insecticide. Bt is not a fungicide or a herbicide, which is why the description that emphasizes disruption of feeding and selective action on some insect species best fits.