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兰花怎么用英语写出特征

Orchid Any member of the orchid family (Orchidaceae), among the largest families of plants, estimated to contain up to 35,000 species。 Orchids are monocots; their flowers have inferior ovaries, three sepals, and three petals。 They are distinguished by the differentiation of one petal into a labe...全部

  Orchid Any member of the orchid family (Orchidaceae), among the largest families of plants, estimated to contain up to 35,000 species。
   Orchids are monocots; their flowers have inferior ovaries, three sepals, and three petals。 They are distinguished by the differentiation of one petal into a labellum, and the fusion of pistil and stamens into the column。
   Pollen is usually contained in pollinia, that is, bundles that are removed intact by pollinators, usually insects or sometimes birds。
   Self-pollination and asexual reproduction without fertilization also occur。 The combination of lip and column structure, flower color, fragrance, and other factors may limit the range of pollinators。
   Differing pollination mechanisms often provide barriers to cross-pollination between related species。
   Each flower can produce large quantities of seeds, with numbers in the millions in some tropical species。
   Seeds are minute, with undifferentiated embryo and no endosperm。 Germination and establishment depends on symbiotic mycorrhizae that provide nutrients and water。
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