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angiospermaeЗначение термина angiospermae в knolikangiospermae - angiospermae angiospermae - Flowering plants; sub-division of Spermatophyta. Distinguished from other sub-division, Gymnospermae, by having the ovules borne within a closed cavity, the ovary, formed by the megasporophyll; after fertilization the ovary becomes a fruit, enclosing one or more seeds. Micro- and mega-sporophylls (stamens and carpels) borne in flowers. Gametophyte generations very reduced. Female gametophyte develops entirely within wall of megaspore which at maturity is a large cell containing eight nuclei, the embryo sac. Male gametophyte. initiated by pollen grain (microspore), consists of two non-motile male gametes and a tube cell, within pollen tube. Xylem characteristically has vessels. Includes two classes, Monocotyledoneae and Dicotyledoneae, distinguished by the number of seed leaves (cotyledons) in the embryo, one in the former, two in the latter class. Рядом со словом angiospermae в knolik
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