Mature embryo sac has 8 nucleis.Egg cell has obvious polarity.One synergid degenerates before fertilization, the other does after fertilization.

 
  • 成熟胚囊为八核七细胞,卵细胞极性明显,助细胞在极核融合前已退化一个,另一个宿存,宿存助细胞丝状器明显,并保留退化助细胞的痕迹。
今日热词
目录 附录 查词历史