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Consideration of the characteristics of past and current applied biology reveals its fundamentally ecological nature, and also indicates the potent influence of the applied biologist upon society. It is urged that in order to impress influence upon pupils biological education should be based mainly upon field studies, rather than upon predominantly evolutionary, morphological and physiological studies. The nature of past and existing school biology strongly reinforces the abovel conclusion.
The results of attempts to find and evaluate evidence of the social influences of past and present biological education are presented, both in relation to the whole population, as well as to particular aspects, like food poisoning, the press, and the education of Civil Servants and Members of Parliment.
The potentialities of a Sixth Form biology resting chiefly upon field study are discussed not only as a means of developing an outlook valuable to-day, but also of treating suitably the pre-university education of future applied biologists.  相似文献   

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THE THIOBACILLI,   总被引:3,自引:0,他引:3       下载免费PDF全文
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The structure, assembly, and composition of the extracellular hairs (mastigonemes) of Ochromonas are detailed in this report. These mastigonemes form two lateral unbalanced rows, each row on opposite sides of the long anterior flagellum. Each mastigoneme consists of lateral filaments of two distinct sizes attached to a tubular shaft. The shaft is further differentiated into a basal region at one end and a group of from one to three terminal filaments at the free end. Mastigoneme ontogeny as revealed especially in deflagellated and regenerating cells appears to begin by assembly of the basal region and shaft within the perinuclear continuum. However, addition of lateral filaments to the shaft and extrusion of the mastigonemes to the cell surface is mediated by the Golgi complex. The ultimate distribution of mastigonemes on the flagellar surface seems to be the result of extrusion of mastigonemes near the base of the flagellum, and it is suggested that mastigonemes are then pulled up the flagellum as the axoneme elongates. Efforts to characterize mastigonemes biochemically after isolation and purification on cesium chloride (CsCl) followed by electrophoresis on acrylamide gels have demonstrated what appear to be a single major polypeptide and several differentially migrating carbohydrates. The polypeptide is not homologous with microtuble protein. The functionally anomalous role of mastigonemes in reversing flagellar thrust is discussed in relation to their distribution relative to flagellar anatomy and to the plane of flagellar undulations.  相似文献   

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云南大理洱海之东的砂子箐组产有牙形刺Scaliognathus anchoralis,Gnathodus typicus,Gnathodus cf.girtyi等化石,清楚地表明砂子箐组的地质时代为杜内期.在双廊镇大建旁村环海公路边灰岩中发现牙形刺Lochriea ziegleri,Gnathodus cantabricus,Gnathodus bilineatus remus,Gnathodus bilineatus romulus,充分证明海东地区谢尔普霍夫阶地层的存在.  相似文献   

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