What is Angiosperm?

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Angiosperm:
A vascular plant where fruit and flower formation take place and seed is covered within the fruit is called angiosperm. Such as Oryza sativa, Zea mays.
Fig: Angiosperm flower

Characteristics of Angiosperm:
1. Saprophytic plant and flowery.
2. The saprophyte is differentiated into root, stem, and leaf.
3. The vascular system has true vessel and companion cells in the phloem.
4. The stamens(microsporophyll) and the carpels(megasporophyll) are arranged into a structure called flower.
5. One microsporophyll contains 4 pollen sec(microsporangia).
6. The ovules are enclosed in the ovary at the base of the megasporophyll.
7. Angiosperm are heterosporous i.e.produce two kinds of spores, microspores(pollen grains) and megaspores(embryo sec).
8. A single functional megaspore is permanently retained within the nucellus.
9. The sporophytes are diploid.
10. Spore develop and produce two types of gametophyte, male gametophyte, and female gametophyte.
11. Male gametophyte produces a pollen tube that contains tube nucleus and male gamet.
12. Female gametophyte(embryo sec) contain two poller nuclei(secondary nucleus), three egg apparatus, and antipodal cells.
13. Male gamet non-motil transfare into egg apparatus.
14. Double fertilization and triple fertilization occur in angiosperm.
15. seed remain enclosed in an overy called fruit.

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