首页 > 分享 > 植物学课程课件：第七节花的形态、结构及生长发育.ppt

植物学课程课件：第七节花的形态、结构及生长发育.ppt

花匠小妙招
2024-10-29 01:30

考试提要秋学期理论考试：20%（复习题）秋学期实验考试：15%（认知与操作）秋学期平时成绩：5%（实验报告）冬学期理论考试：40%（花及系统分类）冬学期实验考试：15%（认知与分类技术）冬学期平时成绩：5%（实验报告） Megasporegenesis starts with meiotic division of the diploid megasporecyte 二倍体大孢子母细胞开始减数分裂 Ends with the formation of tetrad of haploid megaspores（单核胚囊）. Of tetrad spores (四分体）only a chalazal one （合点那个）becomes functional--other three degenerate. 3）Development of ovule 胚珠的发育(3) EMC Carex sp. 莎草科苔属 Process of from EMC to tetrad spores in Lilium Process of from EMC to tetrad spores in Zea Types of megasporogenesis大孢子发生的类型 Polygonum type 蓼型(单孢型） In 70% angiosperme, tetrad spores (四分体）only a chalazal one （合点端那个）becomes functional Megaspore (大孢子），other three degenerate点（解体）. Megaspore ------ 3 times of mitosis --- 8 nucleus --- mature (Single nuclear embryo sac embryo sac) seven cells embryo sac includes the egg and two synergids (representing the egg apparatus in the micropylar region of the sac), the central cell and, in the chalazal region, three antipodals. Structure of mature embryo sac 成熟胚囊的结构 three antipodals 反足细胞 the central cell 中央细胞 Synergids 助细胞 chalazal micropylar the egg Orthotropous crassinucellate bitegmic ovules in (Polygonum sp.) . 直生的双珠被、厚珠心胚珠 ? O = obturator, II = inner integument, OT = outer integument, S = synergids, N = nucellus (megasporangium), E = egg cell, SN = secondary nucleus of central cell, ES = embryo sac, A = antipodals, H = hypostase, C = chalaza, VB = vascular bundle, and F = funiculus Structure of mature embryo sac --- megagametophyte 成熟胚囊--- 雌配子体的结构 Seven cells and eight nucleus Anatropous tenuinucellate unitegmic ovule in sedge 莎草的倒生薄珠心胚珠 The drawing portrays structural changes of a sedge (Carex sp.) ovule at three early developmental stages Characterization of mature Megagametophyte 成熟胚囊（雌配子体）的特化 Synergids contain filiform apparatus The egg cell and Synergids are highly polar. Central cell has a big Vacuole (液泡）, and polar Nucle