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北方劳德藻配子和复大孢子的产生 总被引：8，自引：0，他引：8
于１９８６年１０月在厦门近岸采集北方劳德藻，从培养中观察其有性生殖和光对生殖的影响。结果表明，该藻只有宽度为２６－４０μｍ的细胞能形成配子和复大孢子；在光照条件下每昼夜只发生１次性化；雌雄配子以不同发育方式形成，配子发生呈现一定的时间程序；强光照和１６ｈ光周期最适于性化。由此得知，引起性化既依赖适当的细胞大小，又依赖光诱导的外部因素；产生两种精子数目是与精原孢囊的体积大小紧密相关；性化与光强度之间 相似文献
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P.K.S. Shin J.Y.S. Leung J.W. Qiu P.O. Ang J.M.Y. Chiu V. Thiyagarajan S.G. Cheung 《Marine pollution bulletin》2014
Hypoxia likely compromises the reproductive success of those marine organisms carrying out external fertilization because their gametes and embryos are inevitably exposed to the external environment. Hydroides elegans, a dominant serpulid polychaete in Hong Kong waters, can spawn throughout the year but the number of recruits drops during summer when hypoxia commonly occurs. This study attempted to explain such observation by investigating the gamete quality, including sperm motility, egg size, complexity and viability, after 1-h hypoxic exposure (1 mg O2 l−1). In addition, how gamete quality affects fertilization success and embryonic development was examined. After 1-h hypoxic exposure, sperm motility was significantly reduced, compromising fertilization success. Although the eggs remained viable, more malformed embryos and retarded embryonic development were observed. We interpreted that the harmful effect of hypoxia on embryonic development was attributed to the teratogenicity and induced oxidative stress, ultimately causing the reduction in recruitment during summer. 相似文献
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本文报道了霍氏半管藻雄配子形成过程中，减数分裂前后的精母细胞期、双鞭毛体期及精子期细胞的超微结构。各期细胞具有一些共同的细胞器－线粒体、色素体和核糖体。高尔基体在配子的整个发育过程中，均未见到。双鞭毛体后期和精子中出现了溶酶体，观察了各期细胞核形态、结构的变化。鞭毛器轴纤丝具９＋０的微管构型，基体微管排列成“车轮”状，过渡区有一基板。 相似文献
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J.Y.S. Leung S.G. Cheung J.W. Qiu P.O. Ang J.M.Y. Chiu V. Thiyagarajan P.K.S. Shin 《Marine pollution bulletin》2013
Sperm production and motility, fecundity, and egg size, complexity and viability of serpulid polychaetes Hydroides elegans and Hydroides diramphus after 2-week treatment to hypoxia (2 mg O2 l−1) was compared with those under normoxia (6 mg O2 l−1). Despite reduced fecundity, the effect of parental hypoxic exposure on gamete quality was not discernible for both species. However, regardless of their subsequent dissolved oxygen environment, eggs spawned by H. elegans after hypoxic exposure were found to have lower fertilization success, slower embryonic development and a significantly higher yield of malformed embryos than those with a parental normoxic treatment. In contrast, neither fertilization success nor rate of embryonic development was affected for H. diramphus. The results implied that hypoxia was a potential stress reducing the recruitment of H. elegans through non-adaptive epigenetic effect, whereas H. diramphus was a more tolerant species to survive hypoxic events. 相似文献
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