The number of mitochondrion is more less than the endoplasmic reticulum , and the smooth endoplasmic reticulum is the main kind of the endoplasmic reticulum ; golgi bodies and lysosomes emerge in the secondary spermatocyte stage . finally , these organelles change into pre - acrosome vesicles which become acrosome at last . sinopotamon chekiangense during the spermatogenensis , chronmatins condense at different level until middle spermatid stage 在整个发生过程中细胞器数量较少，内质网数目在各细胞器中所占比例最大，以滑面内质网为主，线粒体在初级精母细胞中最多，自次级精母细胞开始逐渐减少，高尔基体和溶酶体自次级精母细胞始出现，在发育过程中上述细胞器不断分化，在精细胞阶段形成前顶体腔，最后形成圆球形顶体。
The main mechanisms of earthworms ' resistance to metal pollutants are also elaborated : ( 1 ) its lipid antioxidative enzyme system helps relieve the stress of oxidation ; ( 2 ) compartment and immobilization of metals ; ( 3 ) process of chelating and detoxicification ; ( 4 ) lysosome and cellular plasmid are activated to restrain activity of heavy metals 并阐述了蚯蚓对重金属的主要耐性机制： ( 1 )脂质过氧化保护酶系统缓解氧化胁迫； ( 2 )分隔、固定作用； ( 3 )螯合解毒作用； ( 4 )溶酶体和细胞质粒抑制重金属活性。
These suggested that so2 may affect body immunity to a certain degree . ( 3 ) effects on mouse thymus of so2 challenge : he staining showed no obvious structure changes of thymus in all treatment groups compaired with the control group ; the ultrastructure of thymus can be seen injured in so2 treated groups from tem observation ( 3 )二氧化硫染毒对小鼠胸腺组织学结构影响较小：用透射电镜观察发现胸腺组织中有部分淋巴细胞变形且异染色质增多，胸腺上皮细胞中可见次级溶酶体增多，线粒体变形，这说明二氧化硫可能对中枢免疫器官也有一定的不良影响。
