【摘要】 利用透射电镜观察刺参的精子发生过程,揭示其从精原细胞到精子的一系列超微结构变化。根据顶体发育的特点,将刺参精细胞发育分为精原细胞、精母细胞、精细胞等3个发育时期。精原细胞体积最大,有明显核仁,出现前顶体颗粒。初级精母细胞略小,染色质开始凝集,次级精母细胞开始出现尾部。精细胞时期顶体颗粒形成,线粒体明显的融合成一巨型线粒体。透射电镜和扫描电镜观察精子结构,成熟精子为原生型,由头部、中部、尾部组成。头部圆形,直径约3μm,围绕头的中部有一环形凹陷沟,尾部长约50~60μm。核染色质凝集成团块状,中部不发达,线粒体融合成1个环绕中部。尾部鞭毛横切面为简单的“9+2”型结构。更多还原

【Abstract】 The ultrastructure and development of sea cucumber (Apostichopus japonicus) was observed by using electronic microscope. Spermatogonium had a distinct nucleolus, and some proacrosomal granules. Chromatin condensation was found during primary spermatocyte phase. The tail emerged in the following stage in spermatid phase. Proacrosomal vesicle formed and gradually developed into an acrosome. Mitochondria gradually fused and increased in size, providing energy for sperm’s movement. Mature spermatozoon belongs to primitive type ,consisting of head , middle piece and tail. The acrosome in the head was spheral in shape, and there was only one mitochondria in the mature sperm .The flagellum had a simple "9 +2" type of microtubular structure.更多还原