中华锯齿米虾卵母细胞卵黄发生的超微结构

利用透射电镜对中华锯齿米虾卵母细胞的卵黄发生过程进行超微结构的研究.结果表明:中华锯齿米虾卵黄发生过程是双源性的.在卵黄发生过程中,卵母细胞中的线粒体、内质网、溶酶体和核糖体等多种细胞器均参与了其内源性合成,其中线粒体最早参与形成卵黄颗粒.在卵黄发生的中后期,内质网成为内源性合成卵黄蛋白最主要的细胞器,并最终演化成颗粒较大且有膜包被的卵黄球;溶酶体也在此时期发挥其特有的吞噬功能,通过融合分解线粒体、内质网等胞质细胞器,最终形成一种十分致密的卵黄球.外源性卵黄则主要通过卵质膜形成的微绒毛和微吞饮小泡从卵周隙及滤泡细胞中摄取外源物质而形成.

Ultrastructure of the Vitellogenesis in the Oocytes of Neocaridina denticulata sinensis

The vitellogenesis of the oocytes in Neocaridina denticulata sinensis was examined by transmission electron microscope.The results indicate that there was a dual origin of the yolk.All kinds of organelles were involved in endogenous yolk formation during the vitellogenesis period,for example,mitochondria,endoplasmic reticula,lysomes and ribosomes.The mitochondria were the first organelles involved in yolk granules formation.However,the endoplasmic reticula were the dominant organelles which played the most important role in the metaphase and anaphase of vitellogenic oocytes and then developed into the bigger yolk granules with membranes.Furthermore,the lysomes play the typical function by engulfing and resolving the mitochondria and endoplasmic reticula in the same phase,at last formed high electron-dense yolk granules.Exogenous yolk formation was carried out primarily by microvillus and pinocytotic vesicles of the plasma membrane which uptook the exogenous materials from the perivitelline space or follicular cells.