The Flower
Short Notes
1.0 The Flower (Reproduction)
Whorls:
- Calyx (Sepals): Protects the bud.
- Corolla (Petals): Attracts pollinators.
- Androecium (Stamen): Male part (Anther + Filament).
- Gynoecium (Pistil): Female part (Stigma + Style + Ovary).
Classification:
- Bisexual: Both sexes present (Rose).
- Unisexual: One sex present (Papaya).
2.0 Pollination & Fertilization
Pollination: Transfer of pollen from Anther → Stigma.
Agents: Wind, Water, Insects, Animals.
Fertilization: Fusion of male cell + egg.
Path: Stigma → Pollen Tube → Style → Ovule.
The Big Transformation:
- Ovary → Fruit
- Ovules → Seeds
3.0 Fruits (The Protectors)
Pericarp (Wall): Epicarp (Skin), Mesocarp (Flesh), Endocarp (Inner pit).
Types:
- Fleshy: Juicy (Tomato).
- Dry: Hard (Pea).
- False Fruit: Grows from the thalamus, not the ovary (Apple).
4.0 Seeds (The Embryo)
Dicot Structure: Seed coat (Testa/Tegmen), Hilum (scar), and Micropyle (pore).
Embryo Parts:
- Radicle: Future Root.
- Plumule: Future Shoot.
- Cotyledons: Food storage.
5.0 Germination (The Growth)
Essential Conditions: Water, Oxygen, and Temp (25°C–35°C).
Types:
- Epigeal: Cotyledons come above ground (Bean).
- Hypogeal: Cotyledons stay below ground (Pea).
- Vivipary: Grows while attached to parent.
- Dormancy: A "sleep" state where the seed waits for right conditions.