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1.
在长期演化的历史进程中.昆虫的成熟卵母细胞获得了由滤泡细胞分泌的卵壳蛋白凝聚固化而成的卵壳所包被起来.卵壳具有保护性等多种生理功能(夏邦颖1982)。在卵壳上有受精孔和和气孔分布,在鳞翅目等昆虫卵壳上的受精孔周围。有受精孔区花饰特征.这种结构对卵在受精时有聚拢精子游向受精孔的作用.昆虫学家们利用卵的受精孔区花饰特征作为昆虫卵分类的依据(D(o|¨)hing 1955,Hinton1970,Downey 1980.1981夏邦颖1980)。笔者在近年的研究工作中注意到昆虫卵由受精孔向卵内延伸的结构——受精孔管.曾在扫描电镜首  相似文献   

2.
昆虫的卵壳   总被引:1,自引:0,他引:1  
介绍昆虫卵壳的表面结构,内部结构,生化特性和卵壳的形成过程,昆虫卵壳表面大多具有受精孔区花饰特征和有气孔分布,依昆虫种类而异,对昆虫卵壳蛋白的氨基酸组成和卵壳中的无机元素的种类和含量,以及维系卵壳的结构力和卵壳蛋白的分类地位,进行了探讨,并阐述昆虫卵壳的形成过程。提出了研究昆虫卵壳既有理论意义,又有实际意义。  相似文献   

3.
革胡子鲶受精过程的扫描电镜观察   总被引:9,自引:1,他引:8  
应用扫描电镜观察和描述了革胡子鲶成熟卵和精子的形态、卵壳膜的表面结构和形态、受精孔的位置和结构、精子入卵过程的程序和变化。讨论了精子入卵过程及精孔细胞在解体之后可能转变为一种能够吸引精子在精孔区聚集的“受精素”物质等问题。  相似文献   

4.
利用扫描电子显微镜对跳甲属Altica北京有分布的7个种的卵的形态结构进行观察和对比研究。结果表明7种卵在卵的大小、卵壳表面纹饰的形状、纹饰突起的程度、孔洞的多少等均存在明显差异。据此探讨了卵的表面形态结构在分类和系统发育中的作用,同时还探讨卵的形态结构与昆虫生境的相关性。  相似文献   

5.
陈仕江  黄天福 《四川动物》1997,16(3):102-104
贡嘎蝠蛾卵呈椭圆形,在扫描电镜下卵壳表面分为一般卵壳区和受精孔区:一般卵壳区密布颗粒状突起;受精孔区位于卵端部,呈不规则梨形垫状,精孔开口于突起内侧凹陷上部。贡嘎蝠蛾在6月下旬—7月产卵,散产。在平均温度8-10℃、相对湿度80%-90%,卵的发育历期为50天左右,孵化率75%以上。卵常遭受霉菌和寄生蜂天敌危害。  相似文献   

6.
为研究繁殖丹顶鹤(Grus japonensis)弃卵原因,对其弃卵与正常卵壳超微结构及化学元素含量进行比较。以2014至2020年在扎龙保护区收集到丹顶鹤弃卵和正常孵化的卵各6枚为研究对象,利用电子扫描电镜观察比较其超微结构,采用电感偶合等离子体光谱仪测量其化学元素含量,并对其卵壳厚度和密度进行测量和比较。弃卵壳厚度、密度分别为正常卵壳厚度、密度的68.0%(P <0.01)和71.5%(P <0.01);弃卵卵壳表面晶体层厚度不均,与栅栏层之间界限不明显,外表皮层有龟裂和条形两种裂纹,栅栏锥体层晶体中有微小球状中空结构和类似溶洞的腔室结构,壳膜层纤维表面的片状突起较少,这些结构均与正常卵壳不同。检测卵壳23种化学元素中,弃卵卵壳Ca、Na、P、Mg和K元素含量显著低于正常孵卵卵壳(P <0.05)。从卵壳结构和元素分析,卵壳元素含量异常、结构和功能缺陷有可能是导致其亲鸟弃卵的原因之一,这与亲鸟占据生境资源情况、与其他鸟类间繁殖压力、食物可获得性和生存对策等交互作用的影响有关。  相似文献   

7.
四种鹭卵壳的超微结构   总被引:5,自引:0,他引:5  
富民等,1996;张琳等,1997),其中鸡形目Galliformes种类最多,约占60%。浙江鹭类有过研究(朱曦等,1988;1994a;1994b;1996),卵壳结构未见报道。本文对鹭科4属4种鹭卵的卵壳超微结构进行观察和比较,供鹭类分类和演化以及亲缘关系研究提供参考。1 材料和方法池鹭...  相似文献   

8.
作为胚胎发育的屏障,卵壳特征如卵壳厚度和气孔密度具有重要的生态学意义。本文研究了高寒草甸繁殖的7种代表性雀形目鸟类角百灵(Eremophila alpestris)、小云雀(Alauda gulgula)、黄头鹡鸰(Motacilla citreola)、树麻雀(Passer montanus)、粉红胸鹨(Anthus roseatus)、黄嘴朱顶雀(Carduelis flavirostris)、赭红尾鸲(Phoenicurus ochruros)的卵与卵壳特征,以探索在高寒缺氧环境下,不同科鸟类的适应性调节。结果发现,7种鸟类中,除小云雀和角百灵之外,其他鸟类的卵与卵壳特征均有显著的种间差异(除卵壳厚度和气孔直径之外);对7种鸟类卵壳厚度、气孔密度、卵体积、卵重之间的线性拟合显示,卵壳厚度、卵体积与气孔密度均无显著相关性(卵壳厚度:P = 0.11,卵体积:P = 0.09),卵重、卵体积与卵壳厚度呈显著正相关(卵重:r2 = 0.46,P < 0.001;卵体积:r2 = 0.44,P < 0.001);对7种鸟类卵的数据与繁殖期雌鸟平均体重的线性拟合结果显示:平均卵重、卵壳厚度的差异与雌鸟体重成正相关(卵重:r2 = 0.66,P = 0.03;卵壳厚度:r2 = 0.92,P < 0.01);对6种鸟类(缺乏粉红胸鹨窝卵数数据)卵的数据与孵卵相关变量的线性拟合结果显示:卵壳厚度及气孔率与窝卵数成负相关(卵壳厚度:r2 = 0.64,P = 0.056;气孔率:r2 = 0.87,P < 0.01),6种鸟类(缺乏树麻雀巢杯指数数据)气孔率与巢杯指数或巢型无显著相关性(巢杯指数:P = 0.49,巢型:P = 0.435)。卵表面积和总气孔数解释了大部分气孔率差异(87%),卵重和气孔率与孵卵期无显著相关(P = 0.77),气孔率显著低于预期气孔率(P<0.001)。这些结果表明,种间的遗传性(如成鸟的形态、窝卵数等)决定了大部分卵与卵壳特性的差异,但是为适应高寒低氧的气候特征,不同种的鸟都具有相对厚的卵壳和低的气孔率特征,说明环境因素同样影响卵的进化。另外,单纯的卵特性(卵体积和气孔率)并不能决定孵卵期的长短,亲鸟的孵卵行为同样具有重要的影响,角百灵虽然离巢频率相对较高,但是孵卵期却相对较短,这可能与其较高的气孔率有关。  相似文献   

9.
作者以两性融合发育鱼为对照,对雌核发育银鲫卵壳的表面结构及其可溶性蛋白的组成进行了研究:(1)雌核发育银鲫卵壳表面比较平滑,没有明显的嵴和沟;(2)雌核发育银鲫卵壳可溶性蛋白的含量略高于两性融合发育鱼,并且在Ⅱ区段存在一条分子量为10Dalton的特异蛋白区带。并对银鲫卵壳结构及组成的特殊性和银鲫卵初级控制作用间的关系进行了初步探讨。  相似文献   

10.
三种海鸟卵壳的超微结构和无机成分的研究   总被引:4,自引:0,他引:4  
应用扫描电镜和TN-5500能谱仪对三种海鸟卵壳的超微结构和基本无机元素进行研究分析,结果表明,基本结构相似,但表层突起和裂纹,乳锥和锥本形态,以及气孔在单位面积内的数量,壳膜与卵壳的锚连方式,壳膜元素组成等都存在着不同,这既反映其遗传,繁殖生理功能上的差异,也显示了不同种鸟卵壳之间的相似和相异性,因而对研究严分类和地理分布具有一定差异价值。  相似文献   

11.
We report here the fine structure of the eggs of blowflies Aldrichina grahami (Aldrich) and Chrysomya pacifica Kurahashi. For A. grahami, the plastron is wide and extends to almost the entire length of the eggs. The plastron near the micropyle is truncated. The polygonal patterns of chorionic sculpture bear a distinct swollen boundary. Regarding C. pacifica, the plastron is narrow and extends to almost the entire length of the eggs. The plastron near the micropyle bifurcates to a Y-shape, but the arms of the 'Y' are short. Information presented herein allows some distinctive features to differentiate among eggs of blowfly species.  相似文献   

12.
The eggs of five species of Delia have been examined for the external chorionic patterning, the size and shape of the micropyle and the number, characteristics and distribution of the aeropyles using the scanning electron microscope. The species concerned are the cabbage root fly Delia radicum , the onion fly Delia antiqua , the seed corn maggot Delia platura , the wheat bulb fly Delia coarclata and the turnip fly Delia floralis.
Each species has its own clear characters and this, coupled with a significant difference in egg size, enables one species to be distinguished from another.  相似文献   

13.
The fish egg is surrounded by a thick envelope called the chorion. The fertilizing spermatozoon enters the egg through a canal-like structure in the chorion, the micropyle. Examination of micropyle at fertilization is difficult if eggs are large and have no distinct landmarks surrounding the micropyle, or if they are positively buoyant in water. Eggs of many commercially important fishes (e.g., flounder, sea bream and eel) are buoyant in water or only slightly adhere to solid objects (e.g., sands, rock and water plants), which makes observation of spermatozoa at fertilization difficult. Here, we report that such eggs can be firmly attached to plastic and glass dishes that have been previously coated with poly-L-lysine. These adhering eggs can be fertilized and develop normally on the dishes. Observations of micropyles of three fish species, before and after sperm entry are presented.  相似文献   

14.
The eggs of Palingenia longicauda (Ephemeroptera : Palingeniidae) were studied by scanning electron microscopy (SEM), and showed a biconvex shape with the 2 aspects joined along a thick peripheral border. The eggs were completely wrapped by an exochorion that differs in thickness and organization according to the region of the chorionic surface. The thickest part of the exochorion formed a plaque, which also covered part of the peripheral border, and was constituted of a network of filaments. The remaining part of the exochorion was composed of a thin wrinkled sheet. The micropyle, hitherto unknown in Palingeniidae, appeared as a round opening penetrating into the plaque. The fibrillar network surrounding the micropyle dove-tailed with the egg chorion, forming a differentiated raised process. This peculiar interconnection facilitates egg anchoring to the substratum, and is an adaptation of the fibrous coat to the aquatic environment.  相似文献   

15.
The micropyles and their surrounding structures of pelagic fish eggs of nine species were examined and compared using a scanning electron microscope (SEM). The surface of the egg membrane possesses uniformly distributed pores. However,Lateolabrax japonicus possesses a number of small knobs. The region of the micropyle of fish eggs examined is characterized by a circular elevation in which the pores are larger than those on the other parts of the egg membrane. In contrast,Kareius bicoloratus egg has no elevation and possesses uniform pores to the edge of the micropylar canal. The funnel-like structure is seen in the opening of the micropyle inSardinops melanostictus, Saurida elongata, Sillago japonica, Parapristipoma trilineatum, Hypodytes rubripinnis andK. bicoloratus. These specific features of the micropyle may be used for the identification of pelagic eggs.  相似文献   

16.
Starry flounder Platichthys stellatus, spotted halibut Verasper variegates, turbot Scophthalmus maximus, and Japanese flounder Paralichthys olivaceus are four commercially cultivated multiple spawning flounders that spawn pelagic eggs. Through appropriate light and scanning electron microscope processing, the shape and surface structures (such as micropyle, pores, pore density, and paten) of unfertilized mature and fertilized developing eggs of the four species were observed and measured. First, individual or intraspecific comparisons of the surface structures of eggs at different developmental stages were made. Second, interspecific differences among the four species at the same developmental stage of unfertilized mature eggs were statistically computed and analyzed through one-way analysis of variance and hierarchical cluster analysis. Eggs of the same species collected at different stages of development tend to be different in morphology. Smoothing of the convoluted egg envelope surface and closure of the micropyle to serve as a final step of the polyspermy-preventing reaction are common after fertilization. Based on detailed morphology of micropyle of just-mature fertilizable eggs, turbot, starry flounder, and Japanese flounder each have a micropyle with a long canal but no distinct micropylar vestibule, type III of Riehl and Götting (Arch Hydrobiol 74:393–402, 1974). In contrast, spotted halibut has a micropyle with a distinct flat micropylar vestibule and a long canal, type II. Envelope surface microstructures, especially those in the micropyle region, are useful characters for egg identification among the four species. Cluster analysis using selected egg characters indicated the highest similarity between turbot and Japanese flounder and that starry flounder is obviously more similar to turbot and Japanese flounder than to spotted halibut.  相似文献   

17.
P. Bartsch    R. Britz 《Journal of Zoology》1997,241(3):589-592
Breeding of Polypterus , the most basal living actinopterygian, provided the opportunity to study the surface structure of its eggs with SEM for the first time. The investigation revealed the previously overlooked presence of a micropyle at the animal egg pole, thus rejecting recent textbook belief that the eggs of Polypterus slack a micropyle. Comparison with data for other gnathostomes demonstrates that eggs with a micropyle are a further synapomorphy for Actinopterygii and confirm membership of the Cladistia in that group.  相似文献   

18.
Synopsis We investigated the ultrastructure of the egg membrane surface (unfertilized egg) of Hypophthalmichthys molitrix using scanning electron microscopy. The eggs of silver carp like most other teleosts are surrounded by a relatively thick egg membrane, and have a type III micropyle at the animal pole. The micropyle is almost circular in shape and the micropyle canal is located in its center. The micropyle region is not flat. Round or oval accessory pores are also observed in the canal. The surface of zona radiata is wavy and uneven with a uniform distribution of almost round pores with lips. Microvilli like structure are found in the pore opening region.  相似文献   

19.
Eggs of bony fishes are enveloped by an egg envelope (chorion) in which a micropyle is present near the animal pole. Therefore, sperm penetration into the eggs is limited to the sperm entry site (SES), a region of plasma membrane just beneath the micropyle. In rose bitterling eggs, the SES transforms from a tuft of microvilli into a swollen mass (SM) that continues to plug the micropyle after sperm penetration. The present observations using the rose bitterling Rhodeus ocellatus ocellatus were conducted to examine: 1) whether or not sperm penetration is necessary for formation of the SM and 2) whether or not actin microfilaments are involved in the formation of the SM. Water activation without sperm transformed the SES from a tuft of microvilli into the SM, although it took a longer time for the transformation and the SMs were smaller than in the case of inseminated eggs. The SES presumably has the ability to transform into the SM upon activation of eggs in the present species. Cytochalasin B, which acts on actin microfilaments, did not prevent formation of the SM, irrespective of insemination or activation. The present observations suggest that sperm penetration is not necessary for SM formation and actin microfilaments do not participate in SM formation. © 1996 Wiley-Liss, Inc.  相似文献   

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