词条 | 雄球花 |
释义 | 又称小孢子叶球.裸子植物的雄花序,着生在当年春季新生长枝的基部,它是由多数鳞片(或称小孢子叶即雄蕊)组成,紧密螺旋排列在雄花轴上,呈长圆形或长椭圆形,雄球花在每一个鳞片的下面(背面),具有两个或多个长形的花粉囊(即小孢子囊)。花粉囊内有多个花粉母细胞(即小孢子母细胞),经过减数分裂,产生很多单倍体的小孢子,进而发育为成熟的花粉粒(即雄配子体前期)。每个花粉粒有两层壁,外壁向两侧突出形成两个半球状的气囊(翅);气囊是帮助散布的结构.当花粉成熟开裂时,散出大量具翅的黄色花粉粒,随风传播,最远可达数十至数百公里.这是风媒花植物的一种特化和对环境适应的表现.GOOGLE英文翻译:Also known as the small strobilus. Gymnosperms, the male inflorescence, the students in the spring of that year the new growth of branches of the base, it is by a majority of scales (or small sporophyll or stamens), with a close male flowers arranged in spiral axis, showing Long round or oblong, male cone scales spent on each of the following (the back), with two or more elongated shape of the pollen sac (ie, a small sporangium). Pollen capsule has more than one pollen mother cells (ie, microspore mother cells), after meiosis, resulting in a small number of haploid spores, and then develop into mature pollen grains (ie, the early male gametophyte). Each pollen grain has two walls, the outer wall to form two hemispherical sides highlighted the airbag (fin); airbag is to help spread structure. When mature pollen cracking, the Guggenheim Museum in Bilbao a large number of winged yellow pollen, wind communication, as far as up to tens to hundreds of kilometers. It is wind-pollinated flowering plants as a specialization and adaptation to the environment performance. |
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