Bt Crops - Bt Cotton, Bt Brinjal - Unsolved Practice Set
Chapter: Biotechnology and Its Applications | Topic: Bt Crops Bt Cotton Bt Brinjal
BT CROPS - BT COTTON, BT BRINJAL - UNSOLVED PRACTICE SET
Topic: Bt Crops Bt Cotton Bt Brinjal
Multiple Choice Questions
Q1. Bt crops are genetically engineered to express a toxin gene originally derived from the bacterium:
- Escherichia coli
- Bacillus thuringiensis
- Agrobacterium tumefaciens
- Rhizobium
Q2. The Bt toxin protein exists in an inactive form within the bacterium and becomes active (toxic) only when it enters:
- The plant's roots
- The alkaline gut of certain insect larvae feeding on the plant
- Human digestive system
- Soil bacteria
Q3. Bt cotton was primarily developed to provide resistance against:
- Fungal diseases
- The cotton bollworm, a major insect pest
- Drought conditions
- Excess soil salinity
Q4. Bt brinjal was engineered to resist attack by:
- Aphids
- The fruit and shoot borer insect pest
- Root nematodes only
- Powdery mildew fungus
Q5. One major benefit associated with cultivating Bt crops is:
- A significant increase in required chemical pesticide use
- A reduction in the need for chemical pesticide application against specific target pest
- Complete elimination of all crop pests worldwide
- No effect on pest management at all
Short Answer Questions
Q6. What is the source of the toxin gene used in Bt crops, and why is this bacterium significant in biotechnology?
Q7. Explain why the Bt toxin is harmless to the bacterium itself but toxic to certain insect larvae.
Q8. Name the specific pest that Bt cotton was developed to resist.
Q9. Name the specific pest that Bt brinjal was developed to resist.
Long Answer Questions
Q10. Explain the mechanism by which the Bt toxin protein specifically targets and kills certain insect larvae, while remaining harmless to the bacterium producing it and to non-target organisms.
Q11. Discuss the development and agricultural significance of Bt cotton and Bt brinjal, explaining how these crops help farmers manage specific insect pests.
APPLICATION / ANALYSIS
Q12. A cotton farmer who previously relied on frequent chemical pesticide spraying to control bollworm infestations switches to growing Bt cotton instead. Explain, using your understanding of Bt technology, how this change could affect both pest control and the farmer's use of chemical pesticides.
Q13. A student wonders why the Bt toxin, which is effective at killing certain insect larvae, does not harm humans who consume Bt crop products. Explain, using your understanding of the Bt toxin's mechanism of action, why this selective toxicity occurs.