Heterospory_Seed_Habit_Pteridophytes.pptx

ppt on heterospory

1. Heterospory and Seed Habit in Pteridophytes Overview and Evolutionary Significance

2. Introduction to Pteridophytes • Definition of Pteridophytes • General characteristics • Examples (e.g., Selaginella, Lycopodium)

3. What is Heterospory? • Definition of Heterospory • Difference between Homospory and Heterospory • Examples of heterosporous plants

4. Types of Spores in Heterospory • Microspores (Male) • Megaspores (Female) • Size and function of each spore type

5. Heterospory in Pteridophytes • Occurrence of heterospory in Pteridophytes • Examples: Selaginella, Isoetes, Marsilea

6. Seed Habit in Pteridophytes • Definition of seed habit • How heterospory led to seed habit evolution • Pre-adaptations for seed habit

7. Evolution of Seed Habit • Transition from free-sporing plants to seed plants • Importance of retained megaspore in evolution • Adaptive advantages of seed habit

8. Examples of Heterospory & Seed Habit • Selaginella • Marsilea • Isoetes • Azolla

9. Homospory vs. Heterospory • Comparison table • Key differences • Significance in plant evolution

10. Reproduction Process in Heterosporous Pteridophytes • Gametophyte development • Fertilization process • Formation of embryos

11. Conclusion • Summary of key points • Importance of heterospory in plant evolution • Role of Pteridophytes in seed plant evolution

12. References & Acknowledgments • Sources used • Acknowledgments