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1.
黑脊倒刺鲃精巢结构和精子发生的研究   总被引:9,自引:0,他引:9  
用光学显微镜和电子显微镜研究了黑脊倒刺鲃精巢的组织结构和精子发生过程。精巢属于小叶型,由精小叶、小叶间质、壶腹腔和输出管构成。精小叶由各期生精细胞和支持细胞构成。除初级精原细胞以外的各期生精细胞和支持细胞组成了精小囊。每一精小囊中的生精细胞发育同步。成熟的精子从精小囊中释放出来,进入小叶腔中。在精巢的腹侧,小叶腔与壶腹腔连接。在壶腹腔的外侧,有一条与壶腹腔平行的输出管。壶腹腔与输出管相通。在壶腹腔和输出管中都充满精子。精巢的后端与贮精囊相连。贮精囊中充满形状不规则的腔隙。腔隙中有精子分布。输出管从精巢延伸出来,进入贮精囊中,位于贮精囊的一侧。左右两个贮精囊通向一条共同的输精管。输精管上皮具有分泌功能。精子发生在精小叶中进行。精子发生经历了初级精原细胞、次级精原细胞、初级精母细胞、次级精母细胞和精子细胞阶段。精子细胞经过精子形成过程,形成精子。  相似文献   

2.
池塘养殖是三疣梭子蟹(Portunus trituberculatus)的主要养殖方式,但关于池塘养殖三疣梭子蟹雄体的生长和性腺发育规律尚不清楚。本研究通过定点连续采样,首先系统研究池塘养殖过程中三疣梭子蟹雄体的生长和成熟雄体生殖系统的外观及组成的变化,其次研究池塘养殖三疣梭子蟹雄体性腺发育过程中性腺各部分组织学特征及其指数的变化,以及不同月份雄体性腺发育的情况和比例。结果表明:(1)三疣梭子蟹雄体的体重和壳宽增长率及特定增长率均在8月份最高,且体重与壳宽呈显著正相关关系。(2)三疣梭子蟹成熟雄体的生殖系统由体外(阴茎、交接器)和体内(精巢、输精管)两部分构成。(3)根据精巢和输精管的外观、组织学特征及其指数的变化,可将三疣梭子蟹雄体性腺发育分为3期。精子发生期,即精巢内主要细胞类型是精原细胞和初级精母细胞,精巢指数为0.07%~0.16%,此时输精管呈透明状,肉眼很难发现;精荚形成期,精巢内主要细胞类型为次级精母细胞和精子细胞,精巢指数为0.10%~0.51%,输精管内有大量精荚和分泌物,输精管指数为0.01%~0.41%;成熟期,精巢内主要细胞类型是精子细胞和成熟精子,精巢指数为0.10%~0.41%,输精管进一步膨大,输精管指数为0.20%~0.65%。(4)在雄体性腺发育期间,性腺指数和输精管指数呈显著上升趋势,而精巢指数呈现先上升后下降的趋势,且统计分析发现性腺指数与肝胰腺指数无明显的相关性。(5)池塘养殖雄体性腺发育不同步,7月份主要处于精子发生期,8月底,有76%的雄体性腺发育达到精荚形成期,至9月底,达到成熟期雄体的比例为47%,此后雄体性腺发育趋于成熟,10月中下旬至12月份池塘养殖雄体均主要处于成熟期。  相似文献   

3.
应用电镜技术对蕨类植物绵马鳞毛蕨(RYOPTERIS CRASSIRHIZOMA Nakai)精母细胞和游动精子的超微结构特征进行了研究。精母细胞为多边形,细胞质内含有丰富的线粒体、质体、内质网、高尔基体等常见的细胞器.在细胞质中还可见到一些同心圆膜状结构,位于质膜的附近或精母细胞的角偶。同心圆膜状结构由双层膜环绕构成,外被l层单位膜。精母细胞与精子器的璧细胞之间形成了分离腔。在精母细胞质膜外形成了嗜锇层,这些结构的形成说明精母细胞已经开始与雄配子体逐渐分离,进入独立发育的阶段。尽管精母细胞之间也有嗜锇层的形成,但嗜锇层是不连续的,其上有一些空隙,精母细胞之间可通过空隙进行物质和信息的交流。成熟的精子细胞外被l层透明的薄膜,里面为游动精子。螺旋状。由环状细胞器环绕3~4圈构成.这些环状细胞器包括多层结卡构、微管带、巨大线粒体、鞭毛带和1个长形浓缩的细胞核。游动精子的后端为一些泡囊化的细胞质.其中包括一些残存的线粒体、造粉质体及大的囊泡等。当成熟的精子细胞排出精子器后。其内的游动精子挣脱透明质膜的束缚,摆脱后端的囊泡,成为1条游动精子。本文还对绵马鳞毛蕨和其它蕨类植物精子的超微结构特征进行了比较。  相似文献   

4.
中国淡水蛏精子发生的超微结构研究   总被引:13,自引:3,他引:10  
利用透射电镜观察了中国淡水蛏的精子发生和精子结构。描述了精子发生过程中各细胞形态结构的变化;揭示了细胞核、线粒体和项体等的演变过程。中国淡水蛏的精子经过精原细胞、初级精母细胞、次级精母细胞和精子细胞,最终限育为成熟的精子。精子为典型的原生型,由头部、中段和尾部构成。项体复合体位于精子头部前端,呈“⊥”形,精核近圆形;中段包括2个中心粒和4或5个紧密排列的椭圆形线粒体;尾部鞭毛断面为典型的“9+2”  相似文献   

5.
长吻鮠精巢发育的分期及精子的发生和形成   总被引:11,自引:0,他引:11  
长吻鮠精巢的发育分为精原细胞增殖期、精母细胞生长期、精母细胞成熟期、精子细胞出现期,精子完全成熟期和精子退化吸收期。精巢的后1/3不产生也不贮存精子,精子的发生和形成经过精原细胞、精母细胞、精子细胞到精子的一系列过程。精原细胞有两种类型。精子无顶体,有中心粒帽,中片长,核凹窝和线粒体发达,鞭毛具侧鳍。  相似文献   

6.
东方扁虾雄性生殖系统的解剖学和组织学研究   总被引:5,自引:0,他引:5  
东方扁虾雄性生殖系统由精巢、输精管及雄性生殖孔三部分组成,输精管可分为前、中、后三段。精巢由卷绕的前、后收集管及持靠其上的许多生精腺囊所组成。同一腺囊内的精细胞发生基本同步,而不同腺囊内则可以不同步。收集管的主要功能是将精细胞团输送至输精管。精荚在输粗管内运行时一直进行着精子的形成过程,直至精子成熟。位于输精管末段不肌层外的索带状细胞团被认为是造雄腺。  相似文献   

7.
秦岭北坡中国林蛙精巢显微结构的年周期变化   总被引:6,自引:0,他引:6  
用光镜观察了秦岭北坡中国林蛙(Ranachensinensis)精巢显微结构的年周期变化,结合精巢系数的变化探讨其生殖规律。结果显示,秦岭北坡中国林蛙的生精周期属于非连续型。精巢系数的变化与精子发生的活动周期相一致。精子发生从每年5月开始,翌年4月结束,历时1年。生精周期可划分为5个时期。Ⅰ期,精原细胞增殖期,5~7月,精巢系数最小,精原细胞进行有丝分裂;Ⅱ期,精母细胞成熟分裂期,8~9月,精巢系数最大,精原细胞、精母细胞和精子细胞在生精小管内共存;Ⅲ期,精子形成期,9~1 0月,精子细胞变态形成精子;Ⅳ期,成熟精子贮存越冬期,1 1月至翌年2月,成熟精子贮存在生精小管中;V期,精子排放期,翌年3~5月,精巢系数显著下降,成熟精子从生精小管脱离,通过输精管道排出体外。  相似文献   

8.
应用光镜和透射电镜技术研究山羊精子发生不同阶段各级生精细胞显微、超微结构及山羊精子分化成熟过程。结果表明:山羊精子发生经历了精原细胞、初级精母细胞、次级精母细胞、精子细胞及变态精子阶段发育成成熟的精子。精原细胞期核呈椭圆形,染色质凝集成团分布于核质中,线粒体开始出现;精母细胞期有高尔基体分布;精子细胞经过核质浓缩、线粒体迁移等过程发育成成熟精子,成熟的山羊精子头部细长,核质高度浓缩,中段膨大,线粒体丰富。线粒体、中心粒对精子变态发生起重要作用,同时观察到头部与中段脱落的畸形精子。  相似文献   

9.
优雅蝈螽与暗褐蝈螽精子束的显微观察   总被引:2,自引:1,他引:1  
本文应用微分干涉相衬法对优雅蝈螽Gampsocleis gratiosa Brunner von Wattenwyl和暗褐蝈螽G. sedakovii (Fischer von Waldheim) 雄性精巢管基部、输精管、贮精囊和精包,及雌性受精囊中精子束的形态变化进行了观察,对探讨螽斯近缘种的生殖隔离机制和生殖生物学具有重要意义.结果表明:这两种蝈螽的精子束通过精包转移到雌性受精囊后,精子束的形态发生了显著变化.精巢管基部的精子为游离的单个精子;输精管、贮精囊和精包中精子成束排列形成较分散的精子束,精子束头部包裹有粘液帽;雌性受精囊中的精子束的精子呈羽状排列,精子的头部汇集在中央轴上.两种蝈螽精子束形态差异不显著.  相似文献   

10.
贻贝雄性生殖系统的组织学和超微结构   总被引:17,自引:0,他引:17  
贻贝雄性生殖系统中精巢由树枝状的生殖管,输精管民。生殖管反复分枝成生精小管而末端膨大的泡囊,二者皆由位于基膜上的生殖上皮和管壁上皮构成,生殖上皮是由圆形或卵圆形的精原细胞组成,精原细胞最大,核内染色质稀疏,靠核膜内侧分布,核仁一个,明显。初级精母细胞上,染色质开始集成小团块,线粒体向细胞的一侧集中,次级精母细胞与表母细胞结构相似,染色质浓缩成数大块,核膜或散布于核内,精细胞内开始出现顶体颗粒并逐渐  相似文献   

11.
通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.  相似文献   

12.
The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.  相似文献   

13.
Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m−2 s−1. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to Pfr.  相似文献   

14.
龙胆科药用植物化学成分的研究现状   总被引:16,自引:0,他引:16  
龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。  相似文献   

15.
16.
Summary Embryogenic tissues of sugi (Cryptomeria japonica) were induced on a modified Campbell and Durzan (CD) medium containing 1 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 600 mg l−1 glutamine, and subcultured in the medium of the same composition for over 1 yr. This resulted in a mixed culture of embryogenic and non-embryogenic cells. When embryogenic cells were isolated and cultured independently, their capacity to form embryogenic aggregates was lost. Thus, the non-embryogenic cells present within a mixed culture system were essential to the formation of embryogenic aggregates. When embryogenic tissues were isolated and cultured independently on a high glutamine-containing (2400 mg l−1) medium, dry weights and endogenous levels of glutamine increased, and the tissue could generate a large number of embryogenic aggregates. Amino acid analysis of embryogenic and non-embryogenic cells from the maintenance culture indicated a higher level of glutamine was present in the latter. The high endogenous level of glutamine in the non-embryogenic portion of mixed cell masses may be the supplier of glutamine for maintaining the embryogenic property of the tissues.  相似文献   

17.
The review deals with study of enzymologic properties of a novel highly specific acetylcholinesterase substrate, N-(β-acetoxyethyl) piperidinium iodomethylate (“piperidylcholine”), and its 30 derivatives that were tested as effectors of cholinesterases of mammals and various species of Pacific squids. It was proven for the first time that responsible for specificity of action was structure of cyclic ammonium grouping of the alcohol part of molecule of the ester substrate. Analysis of specificity is performed based on enzymatic hydrolysis parameters—activity of catalytic center of cholinesterases and bimolecular constant of the reaction rate that are determined at optimal and low substrate concentrations. Among the specially synthesized group of thioester compounds there is revealed one more highly specific acetylcholinesterase substrate—N-(β-acetoxyethyl) piperidinium.  相似文献   

18.
A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.  相似文献   

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20.
真菌类遗传学分析的知识结构教学   总被引:5,自引:2,他引:3  
罗桂花 《遗传》2002,24(3):349-350
本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.  相似文献   

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