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现代苏铁的精子细胞仍保留游动鞭毛及小叶幼时旋转的原始特征,与蕨类植物相似。花无假花被,次生木质部无导管与麻黄目与买麻藤目不同。侧生根具固氮功能的珊瑚状根(coralloid root);含苏铁苷(cycasin),叶柄基部具欧米伽“”形的维管束,初生厚壁分生组织细胞离心发生等特征又不同于银杏目、松杉目、罗汉松目、红豆杉目。现代苏铁类植物约209种,被归入到11个属,3个科(狭义的)中,零星分布于热带与亚热带地区。具体分为:
The sperm cells of modern cycads retain the original features of migratory flagella and small leaflets when young, similar to ferns. Flower without perianth, secondary xylem without catheter and ephedra head with buy Maneng different. Coralloid root with nitrogen fixation at the lateral root, vascular bundle with cycasin and omega-shaped base at the base of petiole, eccentricity of primary thick wall meristematic cell, Coniferous, Podocarpus, Taxus. About 209 species of modern cycads belong to 11 genera and 3 families (narrowly defined), sporadically distributed in tropical and subtropical regions. Specifically divided into: