Plant Breeding — Class 12 Bio-Botany (Samacheer Kalvi)
TN State Board (Samacheer Kalvi) Class 12 Bio-Botany, Chapter 9. Hybridisation, mutation breeding, polyploidy and GM crops.
1. About this chapter
This chapter covers Plant Breeding as part of the Class 12 Samacheer Kalvi Bio-Botany curriculum. It deals with hybridisation, mutation breeding, polyploidy and gm crops and builds conceptual understanding essential for the TN HSC Public Exam.
By the end of this chapter, students will be able to:
- Describe methods of plant breeding
- Explain the significance of GM crops
2. Key concepts
- Concept 1: Describe methods of plant breeding.
- Concept 2: Explain the significance of GM crops.
3. Important terms and formulas
| Term / Formula | Description |
|---|---|
| Describe methods of plant… | Describe methods of plant breeding |
| Explain the significance of… | Explain the significance of GM crops |
4. Worked examples
Example 1. Applying a key concept from this chapter.
Solution: Identify the relevant principle → apply the formula or rule → state the answer with correct units.
Example 2. A typical exam-style question on plant breeding.
Solution: Break the problem into steps, use the appropriate formula and verify the answer.
5. Common mistakes
- Mistake: Skipping units or forgetting to state them. Fix: Always write units alongside every quantity and answer.
- Mistake: Confusing similar terms or concepts in this chapter. Fix: Make a comparison table of the terms during revision.
6. Practice (exam-style)
- Define the main term or principle covered in Chapter 9.
- Give two real-life examples related to plant breeding.
- Solve a short numerical or descriptive question from this chapter.
- State one important formula and explain each symbol.
7. Answer key (hints)
- Refer to section 2 (Key concepts) above for the definition.
- Examples should be drawn from daily experience and local context.
- Apply the formula from section 3, show all steps clearly.
- Formula with units — refer to the textbook glossary for symbol meanings.
8. Quick revision
- Class 12 Bio-Botany — Chapter 9: Plant Breeding.
- Core idea: Hybridisation, mutation breeding, polyploidy and GM crops.
- Key outcomes: Describe methods of plant breeding; Explain the significance of GM crops.
- Always revise diagrams / tables from the Samacheer Kalvi textbook before the exam.
