角蝾螺精子的超微结构

用透射电镜(TEM)技术研究了角蝾螺精子的超微结构.成熟精子包括头部和尾部.头部由啤酒瓶状顶体与柱状细胞核构成.顶体内含物分布均匀,电子密度稍低于细胞核;顶体下腔呈细长管状,基部扩大成喇叭形,内有颗粒状物质分布.细胞核物质致密,电子密度高;核的前、后端都有一V字形凹陷,分别为核前窝和核后窝.尾部包括中段和末段.中段由5个线粒体围绕近、远端中心粒构成;末段细长鞭状,由中央轴丝及外包的质膜组成,轴丝为典型的"9+2"结构.比较了角蝾螺精子与相关腹足类精子结构的异同,分析了角蝾螺精子在腹足类系统演化中的地位.

Ultrastructure of spermatozoon of Turbo cornutus Solander

Ultrastructure of mature spermatozoon of the Turbo cornutus was observed by using transmission electron microscopy.The mature sperm contains two parts: head and tail.The head comprises a winebottle-shaped acrosome and a pillar-shaped nucleus.The contents in the acrosome is homogeneous,but the electron density is less than nucleus;the subacrosomal space is long-tubule in shape,and it becomes trumpet-shaped at base,which is characterized by filling with granular materials.The nucleus is highly condensed;there exist front nuclear pocket and posterior nuclear pocket.The tail is comprised of mid-piece and end-piece.Five mitochondria surrounding the proximal and distal contrioles make up a mid-piece;The slim and whip-alike end piece consists of an central axoneme,which is a typical '9+2' structure,and a plasmamembrane.A comparison was made between the ultrastrucutre of Turbo cornutus and related gastropods,and an analysis of the phylogenetic signifance was also presented in this paper.