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The composition of some 1150 phosphate granules in the digestiveglands of over 40 species of marine prosobranch gastropods hasbeen surveyed using a simple preparation technique and semi-quantitativeSEM x-ray microanalysis. Spectral peaks for Mg, K, Ca, Mn, Feand Zn were compared to that of P. Four major types of phosphategranule can be recognised, each generally characteristic ofa taxonomic grouping: high Mg in archaeogastropods and littorinids,multiple metal in higher mesogastropods, and, in neogastropods,Mg-Ca in muricoideans and high Zn in buccinoideans. At leastone Conus species (C. ventricosus) has high-Mg granules. Somecauses of variation in granule composition are discussed: speculatively,it is suggested a palaeoenvironmental influence seems possible. (Received 5 November 1997; accepted 6 January 1998)  相似文献   

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1. Chemical examination of the cell sap of Nitella showed that the concentrations of all the principal inorganic elements, K, SO4, Ca, Mg, PO4, Cl, and Na, were very much higher than in the water in which the plants were growing. 2. Conductivity measurements and other considerations lead to the conclusion that all or nearly all of the inorganic elements present in the cell sap exist in ionic state. 3. The insoluble or combined elements found in the cell wall or protoplasm included Ca, Mg, S, Si, Fe, and Al. No potassium was present in insoluble form. Calcium was predominant. 4. The hydrogen ion concentration of healthy cells was found to be approximately constant, at pH 5.2. This value was not changed even when the outside solution varied from pH 5.0 to 9.0. 5. The penetration of NO3 ion into the cell sap from dilute solutions was definitely influenced by the hydrogen ion concentration of the solution. Penetration was much more rapid from a slightly acid solution than from an alkaline one. It is possible that the NO3 forms a combination with some constituent of the cell wall or of the protoplasm. 6. The exosmosis of chlorine from Nitella cells was found to be a delicate test for injury or altered permeability. 7. Dilute solutions of ammonium salts caused the reaction of the cell sap to increase its pH value. This change was accompanied by injury and exosmosis of chlorine. 8. Apparently the penetration of ions into the cell may take place from a solution of low concentration into a solution of higher concentration. 9. Various comparisons with higher plants are drawn, with reference to buffer systems, solubility of potassium, removal of nitrate from solution, etc.  相似文献   

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Quantitative thin layer chromatography of structural amino acidswas standardized for the study of shell proteins of 13 speciesof freshwater mollusc. There was slight intraspecific variationbetween individuals, particularly for tyrosine concentrations.No external periostracum was chemically identifiable in theshell of Lymnaea peregra (Müller) and this species showedsome amino acid heterogeneity in different parts of the shell.Despite these intraspecific variations, analysis of variancesuggested interspecific variation in concentrations for almostall the amino acids tudied. Cluster and principal componentsanalysis indicated that the amino acid composition did reflectphylogenetic affinity but that environmental factors were probablymore-important. (Received 5 August 1982; revised 5 August 1982;  相似文献   

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《Ibis》1950,92(2):185-222
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两种品系油菜植株成分与蚜虫种群消长及成蚜翅型的关系   总被引:2,自引:0,他引:2  
本文研究两种品系油菜植株成分与桃蚜(Myzus persicae(Sulzer))、萝卜蚜(Lipaphis erysimi(Kaltenbach))的种群消长及成蚜翅型的关系。经分析得出如下结果:1.桃蚜种群消长与苏氨酸、赖氨酸、组氨酸、丙氨酸、硬脂酸等含量有关;桃蚜成蚜无翅率与精氨酸、谷氨酸、酪氨酸、异亮氨酸等含量有关。2.萝卜蚜种群消长与苏氨酸、蛋氨酸、异亮氨酸、苯丙氨酸、酪氨酸、含水量有关;萝卜蚜成蚜无翅率与含水量。亚麻酸。苏氨酸、油酸,天门冬氨酸、丝氯酸、亚油酸等含量有关。  相似文献   

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两种品系油菜植株成分与蚜虫种群消长及成蚜翅型的关系   总被引:2,自引:0,他引:2  
邹运鼎  杨义和 《昆虫学报》1992,35(2):178-186
本文研究两种品系油菜植株成分与桃蚜(Myzus persicae(Sulzer))、萝卜蚜(Lipaphis erysimi(Kaltenbach))的种群消长及成蚜翅型的关系.经分析得出如下结果:1.桃蚜种群消长与苏氨酸、赖氨酸、组氨酸、丙氨酸、硬脂酸等含量有关;桃蚜成蚜无翅率与精氨酸、谷氨酸、酪氨酸、异亮氨酸等含量有关.2.萝卜蚜种群消长与苏氨酸、蛋氨酸、异亮氨酸、苯丙氨酸、酪氨酸、含水量有关;萝卜蚜成蚜无翅率与含水量.亚麻酸.苏氨酸、油酸,天门冬氨酸、丝氯酸、亚油酸等含量有关.  相似文献   

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中红侧沟茧蜂对植物挥发性物质的嗅觉反应(英文)   总被引:2,自引:0,他引:2  
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Chromosome numbers are reported for 33 species of the tribe Phaseoleae. Six reports are first counts for their species; one report (Ophrestia hedysaroides) is a first count for the genus. This increases the number of genera counted to 53 out of a total 84 for the tribe. A survey of base numbers shows a general pattern of numbers 10 or 11, the same base numbers as in the neighboring tribes Dalbergieae sensu lato, Galegeae sensu lato, and Abreae. The chromosomes are generally small and polyploidy is uncommon. Deviations from base numbers 10 or 11 are mostly found in those genera with morphological pecularities and puzzling taxonomic placements: Erythrina (21), Clitoria (8, 11, 12), Butea (9), Calopogonium (18), Teramnus (14), and Strongylodon (14). Two genera have base numbers which suggest derivation by polyploidy: Glycine (20) and Cologania (22).  相似文献   

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本研究首先是在不同的寄主植物中利用蚜虫性信息素进行田间诱蚜实验。结果表明寄主植物影响性信息素田间诱蚜的种类和效果。在桃园 ,以蚜虫性信息素荆芥内酯和荆芥醇为性诱剂的水盆诱捕器 ,诱到 3种蚜虫的雄蚜 ,分别是桃蚜、桃粉大尾蚜和莲缢管蚜。其中 ,桃蚜占绝大多数 ,且还被性信息素的单一组分植物提取的荆芥内酯所吸引。麦田中诱到的雄蚜为麦二叉蚜。苹果园中诱到的雄蚜是绣线菊蚜和梨中华圆尾蚜 ,且性信息素诱捕器中的数目远多于对照诱捕器。据田间诱蚜实验结果推测 ,荆芥内酯和荆芥醇对桃粉大尾蚜有吸引作用 ,荆芥内酯可能是绣线菊蚜和梨中华圆尾蚜性信息素的一个组分。另外进行的田间实验表明寄主植物挥发性物质对蚜虫性信息素诱蚜效果有影响 ,当荆芥内酯诱捕器同时释放桃叶挥发物时 ,诱到的桃蚜雄蚜数量明显增加。触角电位记录实验也表明桃蚜雄蚜对桃叶挥发物和桃芽挥发物有反应。  相似文献   

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Abstract The behavioral responses of Microplitis mediator were measured in a four‐armed olfactometer. Leaves extract of the suitable host plant of its insect host, cotton, elicited higher olfactory responses; while leaves extract of the less suitable host plant of its insect host, tomato or tobacco, elicited moderate responses. Volatiles from the least suitable host plant of its insect host, hot pepper, elicited the lowest responses. The different preferences to four plant leaves extracts suggested that M. mediator could discriminate between suitable and less suitable host plants of its insect host by semiochemicals. Green leaf volatiles (GLVs), cis‐3‐hexen‐1‐yl acetate, hexanal, and nonan‐1‐ol, are the most attractive compound among the 7 tested compounds. The parasitoids preferred host‐damaged plant to undamaged plant, suggesting that they were able to distinguish between host and non‐host of their insect host through varying chemical blends. Experience with cotton leaves extract prior to experiment enhanced their responses to the same odor.  相似文献   

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