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प्रश्न
Explain the different types of endosperms in angiosperms.
Explain the development of the different types of endosperms in angiosperms.
Describe types of endosperm.
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उत्तर
- Free-nuclear endosperm: This is the most common type. The primary endosperm nucleus divides repeatedly without cell wall formation, and the resulting nuclei remain free in the cytoplasm. Later, walls may form around the nuclei.
Example: Coconut water. - Cellular endosperm: Each nuclear division is immediately followed by cell wall formation, so the endosperm becomes cellular from the very beginning.
Examples: Peperomia, Villarsia, Drimys. - Helobial endosperm: This type is intermediate between the free-nuclear and cellular types. The first division of the primary endosperm nucleus is followed by a cell wall formation that separates the endosperm into a large micropylar chamber and a small chalazal chamber.
Examples: Vallisneria, Erimus.
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