Crop Variety Improvement - Hybridisation and GMO - UNSOLVED PRACTICE SET
Chapter: Improvement in Food Resources | Topic: Crop Variety Improvement Hybridisation GMO
CROP VARIETY IMPROVEMENT - HYBRIDISATION AND GMO - UNSOLVED PRACTICE SET
Topic: Crop Variety Improvement Hybridisation GMO
Multiple Choice Questions
Q1. The process of crossing genetically different plants to produce offspring with desirable traits from both parents is called:
- Cloning
- Hybridisation
- Photosynthesis
- Germination
Q2. Which of the following is a desirable trait that plant breeders try to incorporate into crop varieties?
- Susceptibility to diseases
- High yield and resistance to drought
- Short shelf life
- Sensitivity to fertilisers
Q3. Genetically Modified Organisms (GMOs) are created by:
- Crossing two different plant varieties naturally
- Introducing specific genes from another organism into a plant's DNA using biotechnology
- Growing plants in greenhouses
- Using more fertilisers
Q4. Bt cotton is an example of a genetically modified crop because it:
- Needs more water than normal cotton
- Has been engineered to produce a protein toxic to bollworms, reducing pesticide use
- Grows faster in shade
- Has colourful flowers
Q5. The main advantage of developing crop varieties with shorter maturity duration is that:
- They taste better
- Farmers can grow more than one crop in a year, increasing total annual production
- They need more water
- They become taller
Short Answer Questions
Q6. What is hybridisation? Explain the difference between intervarietal and interspecific hybridisation with one example of each.
Q7. List four desirable traits that scientists aim to develop in crop plants through variety improvement. Why is disease resistance considered particularly important?
Q8. What are Genetically Modified Organisms (GMOs)? Name one GM crop grown in India and explain what genetic modification was made in it.
Q9. Your school garden has tomato plants that are regularly attacked by pests. The biology teacher suggests planting a new pest-resistant variety. Explain how this variety might have been developed - through hybridisation or genetic modification.
Long Answer Questions
Q10. Explain the process and importance of crop variety improvement. Describe the three main approaches: selection from existing varieties, hybridisation (intervarietal, interspecific, and intergeneric), and genetic modification. Why is it important to develop varieties that are high-yielding, disease-resistant, drought-tolerant, and have improved nutritional quality?
Q11. "Genetically modified crops are the future of agriculture, but they also raise serious concerns." Discuss this statement by explaining: how GM crops like Bt cotton and Bt brinjal are created, their benefits (pest resistance, higher yield, reduced pesticide use), and the concerns raised by farmers and environmentalists (impact on biodiversity, safety for human consumption, seed monopoly by companies). What is your balanced view on this debate?
APPLICATION / ANALYSIS
Q12. Case Study — Wheat Variety Development:
Agricultural scientists developed three new wheat varieties:
| Variety | Parent 1 | Parent 2 | New Trait | Yield |
|---|---|---|---|---|
| Pusa-12 | High-yielding Indian wheat | Drought-resistant Mexican wheat | Drought tolerance | 4 tonnes/hectare |
| Pusa-24 | Disease-resistant wild wheat | High-yielding cultivated wheat | Disease resistance | 4.5 tonnes/hectare |
| Golden Wheat | Normal wheat | Gene from daffodil flower | Vitamin A enriched | 3.8 tonnes/hectare |
Answer the following:
(a) Which variety was developed through interspecific hybridisation? How can you tell?
(b) Which variety is a GMO? What makes it different from the other two in terms of how it was created?
(c) If you were a farmer in a drought-prone area of Rajasthan, which variety would you choose and why?
Q13. Real-Life Application — Seed Shop Dilemma:
A farmer in Uttar Pradesh visits a seed shop and sees three options for cotton seeds:
The farmer has 2 hectares of land and a budget of ₹5,000 for seeds.
| Seed Type | Price per kg | Features |
|---|---|---|
| Traditional desi cotton | Rs 200 | Low yield, needs pesticides |
| Hybrid cotton | Rs 800 | High yield, needs fertilisers and pesticides |
| Bt cotton | Rs 1,500 | High yield, pest-resistant, needs licence |
Answer the following:
(a) How many kilograms of each seed type can the farmer buy with his budget?
(b) If the farmer chooses Bt cotton but can only afford seeds for 1 hectare, what are the risks and benefits of this choice compared to planting hybrid cotton on both hectares?
(c) Why do seed companies charge more for Bt cotton seeds? What does this tell you about the economics of modern farming?