人工授精平角涡虫早期胚胎和幼虫的扫描电镜观察

为探明平角涡虫(Planocera reticulata)胚胎发育规律,采用人工授精方法,获得不同发育阶段的无卵外胶膜胚胎,并运用扫描电镜技术,观察了受精卵早期胚胎发育和幼虫发育.结果表明,从第3次卵裂开始表现出螺旋式卵裂的特征.在囊胚时期和原肠时期在动物极顶端有几个卵裂球向内下陷形成一凹陷.浮游幼虫期的幼虫利用体表纤...

Early Embryo and Larva of Planocera reticulata:in Vitro Fertilization and SEM Observation

In order to study the early development of Planocera reticulata,embryos without egg-shell and larva were obtained using in vitro fertilization,and examined by scanning electron microscopy(SEM).Typical spiral cleavage was observed since the third cleavage.Several micromeres at proximal end of animal pole tended to form an invagination during blastula and gastrula stages.Planktonic larva swam freely with the cilia,which were emanated from the epidermal plates.At the ventral surface of larva,a rank of long cel...