2016-06-16 13:33:53

雌球花 免费编辑 添加义项名

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雌球花又称大孢子叶球.裸子植物的雌花序,着生在当年春季新生长枝的顶端,一至两个.由多数鳞片(大孢子叶、也可称心皮或珠鳞)组成,密集螺旋状排列在雌花轴上,并形成长圆形或球形的“果”。

基本信息

  • 中文名

    雌球花

  • 应用学科

    生物

  • 适用领域范围

    植物

  • 表达式

    裸子植物的雌花序

目录

折叠 编辑本段 基本介绍

​ 又称大孢子叶球.裸子植物的雌花序,着生在当年春季新生长枝的顶端,一至两个.由多数鳞片(大孢子叶、也可称心皮或珠鳞)组成,密集螺旋状排列在雌花轴上,并形成长圆形或球形的“果”。雌球花在每片珠鳞的近轴面基部,生有1个至多个裸露的胚珠(大孢子囊),珠鳞并不包裹胚珠.而在每片珠鳞的下面,还生长出一种膜片称苞片或苞鳞.珠鳞在种子形成时,迅速肥大并木质化,掩盖了苞鳞,呈棕色特称为果鳞(宿存或脱落),珠鳞与苞鳞有的是分离的、有的半分离、有的则完全愈合.珠鳞肥大时,顶端加厚形成特殊的突起,在鉴别种类上有重要意义.当花粉飘落在雌球花上,半年后花粉管由珠孔进入胚珠,受精后胚珠形成种子.种子由胚乳、胚和种皮构成,具翅.成熟后球果下垂,称雌球果.GOOGLE英文翻译:Also known as the Great strobilus. Gymnosperms, the female inflorescence, with students in the spring of that year the new growth of branches on top of one or two. By a majority of scales (large spores leaves, skin or beads can also be gratified scales), with a dense spiral female flowers arranged in the shaft, and form a long round or spherical, "fruit." Female cone scales beads per unit spent nearly axial base, gave birth to one to more than one exposed ovule (large sporangium), Pearl scales are not wrapped ovules. Each bead in the following scales, but also grow out of a diaphragm called bracts or bud scales. beads scales in the seed formation, rapid enlargement and lignification to cover up the bud scales, scales brown special fruit known as the (residential deposit or loss), plenty of beads scales and bud scales of separation Some semi-separation, while others completely healed. beads scales mast, the top of the formation of a special thickening processes, in identifying the types of great significance. When the pollen falling ball in the female to spend half a year after the pollen tube entering from the micropylar ovules, ovules will become seeds after fertilization. seeds from the endosperm, embryo and seed coat composition, winged. mature cones hang down, saying that the female cone. 

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