Characteristics of Angiosperms (Flowering Plants)
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Presence of Flowers
- Angiosperms produce flowers, which are the reproductive structures.
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Seeds Enclosed in Fruits
- Seeds develop inside the ovary, which matures into a fruit.
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Double Fertilization
- Unique to angiosperms: one sperm fuses with the egg (zygote), the other with polar nuclei (endosperm).
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Vascular System Well Developed
- Contains true xylem (with vessels) and phloem (with companion cells) for efficient transport.
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Presence of True Roots, Stems, and Leaves
- All plant organs are well differentiated and specialized.
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Ovules Enclosed in Ovary
- Unlike gymnosperms, the ovules are not exposed but protected inside an ovary.
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Pollination Mechanisms Diverse
- Can be wind, water, insect, bird, or animal-pollinated depending on species.
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Lifecycle Shows Alternation of Generations
- Dominant sporophyte generation; highly reduced, dependent gametophyte.
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Rapid Life Cycle
- Compared to gymnosperms, angiosperms grow, reproduce, and mature quickly.
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Fruit Formation
- Ovary converts into fruit after fertilization, aiding seed dispersal.
- Broad Diversity
- Largest plant group (~300,000 species); includes herbs, shrubs, trees, and climbers.
- Monocots and Dicots Classification
- Based on seed leaves (cotyledons):
- Monocots: 1 cotyledon, parallel venation, fibrous roots.
- Dicots: 2 cotyledons, reticulate venation, taproot system.
- Highly Specialized Reproductive Structures
- With stamens (male) and carpels (female), often arranged in attractive, colorful flowers.
- Adaptability to Various Habitats
- Found in deserts, aquatic systems, tropical forests, and temperate zones.
- Endosperm Formation
- Provides nourishment to the developing embryo; formed only after fertilization.
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