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1.
六种蝽象的染色体研究(半翅目:蝽科)   总被引:8,自引:0,他引:8  
张虎芳  郑乐怡 《昆虫学报》2001,44(2):129-135
研究了6种蝽象的核型和减数分裂行为。结果表明:6个种的染色体组成均为2n()=14, 具有X-Y性别决定机制;减数分裂行为比较一致,但在中期-Ⅰ常染色体和性染色体的排列方式具有种的特异性,可为蝽科昆虫的形态分类及系统发育提供有用的证据。  相似文献   

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四种蝽科昆虫的染色体研究   总被引:8,自引:1,他引:7  
郑乐怡  张虎芳 《昆虫学报》1999,42(3):234-240
研究了4种中国蝽科昆虫的核型和染色体的减数分裂行为, 并首次在半翅目中采用核型分析软件对第一次减数分裂中期的染色体进行核型分析。结果表明: 4个种均为2n=14和X-Y性别决定机制; 减数分裂行为比较一致, 但在中期 I 常染色体和性染色体的排列方式各不相同; 核型分析后的结果表现出了种的特异性, 可为蝽科昆虫的形态分类及系统发育提供有用的证据。  相似文献   

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三种辉蝽的核型研究(半翅目:蝽科)   总被引:3,自引:0,他引:3  
本首次研究了采于中国的辉蝽属三个种一辉蝽(Carbula obtusangula Reuter)、北方辉蝽(Carbula putoni(Jakovlev),凹肩辉蝽(Carbula sinica Hsiao et Cheng)的核型,结果表明,三个种均具有典型的蝽科核型即:2n(♂)=14,具有XY性别决定机制,但是三个种的常染色体和性染色体在减数分裂时期的行为以及核型分析的结果和模式图各不相同,而且在北方辉蝽中出现了1-2条超数染色体,这些特点可为辉蝽属昆虫的形态分类及系统发育提供有用的证据。  相似文献   

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通过探讨中国蝽科Pentatomidae辉蝽属Carbula的红角辉蝽Carbula crassiventris(Dallas,1849)和北方辉蝽C.putoni(Jakovlev,1876)的精巢形态和染色体的核型及减数分裂行为,为蝽科昆虫的细胞分类学提供新资料。采用显微形态解剖法和染色体制片法对其精巢和染色体进行观察。结果表明:2种精巢的位置、外被颜色、形状及精巢叶的数目都一致;染色体组成均为2n(♂)=14(12A+XY),具有X-Y性别决定机制。在减数分裂过程中,常染色体前减数分裂,性染色体后减数分裂且无交叉;在中期-Ⅱ,常染色体排列成环状而性染色体在环中央形成假二价体。但是,2个物种在弥散期常染色体的去固缩程度,终变期常染色体双交叉的个数及中期-Ⅰ常染色体和性染色体的排列方式都各不相同。本文证实了蝽科昆虫的减数分裂行为在不同属间、种间可不相同,而且具有一定的属、种间特异性;同时为精巢在蝽类昆虫分类中的作用提供新的资料。  相似文献   

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卷蝽Paterculus elatus(Yang)的细胞学研究(半翅目:蝽科)(英文)   总被引:3,自引:0,他引:3  
本文研究了中国蝽科昆虫──卷蝽 Paterculus elatus(Yang)的核型并采用核型分析软件对第一次减数分裂终变期的染色体进行了该型分析。结果表明:卷蝽的2n=16,具有XY性别决定机制,具有一对m-染色体,在有些细胞中出现一个超量染色体。  相似文献   

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悦目金蛛(Argiope amoena)染色体的观察   总被引:1,自引:0,他引:1  
对悦目金株(Argiope amoena)染色体的数目、形态特征和性染色体组成,进行了核型分析,本实验观察胚胎细胞有丝分裂的C-中期相,悦目金蛛体细胞染色体数目是:雌性2n=26,雄性2n=24,性别决定机制属于XXO型。  相似文献   

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对蝽科Pentatomidae4属5种——广二星蝽Stollia ventralis(Westwood)、黒腹二星蝽Stollia guttiger(Thunberg)、西北麦蝽Aelia sibirica(Reuter)、紫翅果蝽Carpocoris purpureipennis(De Geer)、赤条蝽Graphosoma rubrolineata(Westwood)昆虫减数分裂各期染色体形态结构及行为进行分析。结果表明:蝽科5种进行交叉减数分裂。花束期5种昆虫染色质变化相似,形态种间有差异。中期染色体排列方式相似,核型种间差异大。精子形态相似,弯曲度大小种间有差异。双线期、终变期染色体交叉形态、频率及历程长短反映物种进化程度。紫翅果蝽X染色体碎斑化。  相似文献   

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本文记载了中国25种角蝉的染色体,研究表明染色体的数目、大小及其在减数分裂过程中的行为具有种或属一级的分类特征。该科昆虫染色体的数目变异在n=5到12之间,众数为n=11,另外,n=10的类型也较为普遍。绝大多数种类的性别决定机制为XO型,仅个别种类具有新XY性染色体系统。  相似文献   

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中国两种波腿蝗(蝗总科:癞蝗科)染色体C带核型研究   总被引:4,自引:0,他引:4  
李新江  张道川  王文强 《遗传》2005,27(5):735-740
报道中国两种波腿蝗的染色体C带核型,结果表明:红胫波腿蝗Asiotmethis zacharjini (Bei-Bienko, 1926) 2n ♂ =18, neo-X为亚中着丝粒染色体,其他均为近端着丝粒染色体,染色体除强染的着丝粒C带,S8染色体具强染端部C带带纹,neo-Y染色体还具有一条宽的弱染的近着丝粒端居间C带,性别决定机制是neo-XY ♂型,该种染色体组成和性别决定机制在我国癞蝗中为首次报道,蓝胫波腿蝗Asiotmethis jubatus (Uvarov, 1926) 2n=19♂,均为近端着丝粒染色体,仅具有明显强染的着丝粒C带,性别决定机制是XO ♂型;两种波腿蝗的异染色质含量存在显著性差异(α=0.05)。  相似文献   

10.
山地原花蝽核型研究(半翅目,花蝽科)   总被引:2,自引:0,他引:2  
采用姬姆萨染色压片法,对花蝽科山地原花蝽性细胞进行了核型研究.结果表明该种单倍染色体组成为n=14A+XY,为无交叉减数分裂,性染色体经历后减数分裂,上述核型特征为阐明臭虫型内不同科的系统发育关系具有重要意义.  相似文献   

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K. Hausmann 《Protoplasma》1979,100(2):199-213
Summary The membranes of the pellicle of the ciliatePseudomicrothorax dubius are investigated using thin section electron microscopy and freeze-fracture replicas. The plasma membrane is covered by a surface coat and is connected to the outer alveolar membrane by short, sometimes branched, bridges. The inner alveolar membrane is coated on both sides. The epiplasm lies in intimate contact with the cytoplasmic surface of this membrane, and there is a corresponding deposit on the other surface. This deposit is regularly striated.The epiplasmic layer and the alveoli are interrupted at sites of cytotic activity,e.g., the attachment sites of trichocysts, the cytoproct, and the parasomal sacs. The striated deposit ends where the epiplasm ends, indicating a direct relationship between these two epimembranous layers.There is a deposit along the sides of the first part of the tip of the trichocysts, and in this region the trichocyst membrane is free of intramembranous particles.The membrane of the parasomal sacs has a coat on both surfaces. That on the extraplasmic surface is similar to the surface coat of the plasma membrane. The origin of the cytoplasmic coat is unknown. The cytotic activity of these sacs is indicated by their highly irregular profiles.  相似文献   

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Summary The differentiation of the spermatid, especially in reference to the formation of the flagellum, and transformation of the shape of the nucleus was investigated in the domestic fowl.In the early stage of the spermatid, a prominent Golgi apparatus appears around the centrioles. The Golgi vesicles then surround the axial-filament complex which develops from the distal centriole. These vesicles fuse to form continuous membrane at the earliest stage of flagellar formation, and in the succeeding stage Golgi lamellae are attached to the plasma membrane of the developing flagellum. From these observations, it is assumed that Golgi apparatus may be a source of the membrane system of the flagellum.The microtubules distributed around the nucleus form the circular manchette. The anterior region of the nucleus with the manchette is cylindrical in shape and the posterior region without it remains irregular in shape. When the circular manchette has been completed, the whole nucleus acquires a slender cylindrical shape. The circular manchette then changes into the longitudinal manchette. The nuclei of spermatids without a longitudinal manchette are abnormal in shape. In view of these observations it is assumed that the nuclear shaping of the spermatid may be accomplished by circular manchette and the maintenance of shape of the elongated nucleus by longitudinal manchette.The authors wish to thank Mr. Takayuki Mori for his helpful suggestions and technical advices  相似文献   

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Summary The choriocapillaris is a fenestrated capillary bed located posterior to the retinal pigment epithelium. It serves as the main source of supply to the photoreceptors, retinal pigment epithelium, and other cells of the outer retina. The permeability of these capillaries to intravenously injected ferritin (MW — approx. 480,000; mol. diam. 11 nm) was examined in the mouse, rabbit, and guinea pig, each of which is characterized by a different type of retinal vascularization. In all three species, the bulk of the ferritin remained in the capillary lumina, where it appeared to be blocked at the level of the diaphragmed fenestrae. Some ferritin was present in endothelial cell vacuoles. The results confirm previous work on the rat choriocapillaris and indicate that the barrier function of the choriocapillary endothelium is present even among species in which the retinal circulation differs significantly.Supported by NIH grant EY03418  相似文献   

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