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1.
车前属(Plantago L.)植物生态与进化生物学研究进展   总被引:3,自引:0,他引:3  
郭水良 《植物学通报》2002,19(5):567-574
车前属植物是理论生态学、生理生态学、进化生物学研究的理想材料。本文综述了近年来国内外学者在车前属生态学、进化生物学、系统分类学方面的研究概况。  相似文献   

2.
《医学生物学》是一门重要的医学基础课程,它起着连接高中生物和医学其它基础课程的桥梁作用。教学过程中怎样紧密联系其它基础医学课程和临床医学课程,提高学生学习医学生物学的兴趣与积极性,是改善高等医学院校医学生物学教学质量的关键。笔者分别探讨了讲授绪论部分,细胞学部分以及遗传学部分时与临床医学联系的一些实例,并运用了一些新的教学方法和手段来改善教学效果,从而加深了学生对知识的理解和掌握,并提高了学生的动手能力和独立思考能力。  相似文献   

3.
Darwin Day is an international celebration of Charles Darwin’s birthday, February 12, and is used as an occasion for education and outreach in evolutionary biology. I describe the history and structure of Darwin Day at the University of Tennessee, one of the oldest Darwin Day organizations in the world. I detail past events including speakers, themes, and advertising ideas that have worked for us and suggestions for getting a Darwin Day started. I encourage interested groups especially those at schools, museums, libraries, nature centers, and other institutions to adapt ideas from our organization to fit their own circumstances and to start planning their own Darwin Days for the celebration of Darwin’s 200th birthday in 2009.  相似文献   

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We study evolutionary dynamics in a population whose structure is given by two graphs: the interaction graph determines who plays with whom in an evolutionary game; the replacement graph specifies the geometry of evolutionary competition and updating. First, we calculate the fixation probabilities of frequency dependent selection between two strategies or phenotypes. We consider three different update mechanisms: birth-death, death-birth and imitation. Then, as a particular example, we explore the evolution of cooperation. Suppose the interaction graph is a regular graph of degree h, the replacement graph is a regular graph of degree g and the overlap between the two graphs is a regular graph of degree l. We show that cooperation is favored by natural selection if b/c>hg/l. Here, b and c denote the benefit and cost of the altruistic act. This result holds for death-birth updating, weak-selection and large population size. Note that the optimum population structure for cooperators is given by maximum overlap between the interaction and the replacement graph (g=h=l), which means that the two graphs are identical. We also prove that a modified replicator equation can describe how the expected values of the frequencies of an arbitrary number of strategies change on replacement and interaction graphs: the two graphs induce a transformation of the payoff matrix.  相似文献   

6.
Evolutionary biology presents a bewildering array of phenomena to scientists and students alike—ranging from molecules to species and ecosystems; and embracing 3.8 billion years of life’s history on earth. Biological systems are arranged hierarchically, with smaller units forming the components of larger systems. The evolutionary hierarchy, based on replication of genetic information and reproduction, is a complex of genes/organisms/demes/species and higher taxa. The ecological hierarchy, based on patterns of matter–energy transfer, is a complex of proteins/organisms/avatars/local ecosystems/regional ecosystems. All organisms are simultaneously parts of both hierarchical systems. Darwin’s original formulation of natural selection maps smoothly onto a diagram where the two hierarchical systems are placed side-by-side. The “sloshing bucket” theory of evolution emerges from empirical cases in biological history mapped onto this dual hierarchy scheme: little phenotypically discernible evolution occurs with minor ecological disturbance; conversely, greatest concentrations of change in evolutionary history follow mass extinctions, themselves based on physical perturbations of global extent. Most evolution occurs in intermediate-level regional “turnovers,” when species extinction leads to rapid evolution of new species. Hierarchy theory provides a way of integrating all fields of evolutionary biology into an easily understood—and taught—rubric.
Niles EldredgeEmail:
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7.
医学免疫与病原实验学综合了医学微生物学、医学免疫学和医学寄生虫学的实验,独立为一门新课程。课程内容按照基本实验、综合实验和设计性实验三级设置。设计性实验没有给定题目,要求学生自己拟题。学生必须综合三门课程的理论知识和基本实验技术,设计并完成设计性实验。本课程的教学能达到培养学生基本操作技能、创新思维能力和全面素质的目的。进一步完善后,值得向各医学专业推广。  相似文献   

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A wind of change has swept through palaeontology in the past few decades. Contrast Sir Peter Medawar’s dismissive: ‘palaeontology is a particularly undemanding branch of science’ (as recalled by John Maynard Smith in Sabbagh 1999, p. 158) with ‘Palaeontology: grasping the opportunities in the science of the twenty–first century’, the title of a contribution to a special issue of Geobios by the Cambridge palaeontologist, Simon Conway Morris (1998a). The winds of change have come partly from palaeontologists seeking to broaden the impact of their studies and partly from biologists (neontologists) realizing the contributions that palaeontology can make to their disciplines. Consequently, impressions of past life preserved in stone are coming alive. Fossils are being described and analyzed using new tools and languages as the static fossil record becomes a record of transitions in patterns that can be explained and related to biological, ecological, climatic and tectonic changes. The latest addition is evolutionary developmental biology, or ‘evo–devo’, whose language provides a new basis upon which to interpret anatomical change, both materially and mechanistically. In this review I examine the major contributions made by palaeontology, how palaeontology has been linked to evolution and to embryology in the past, and how links with evo–devo have enlivened and will continue to enliven both palaeontology and evo–devo. Closer links between the two fields should illuminate important unresolved issues related to the origin of the metazoans (e.g. Why is there a conflict between molecular clocks and the fossil record in timing the metazoan radiation; were Precambrian metazoan ancestors similar to extant larvae or to miniature adults?) and to diversification of the metazoans (e.g. How do developmental constraints bias the direction of evolution; how do microevolutionary developmental processes relate to macroevolutionary changes?).  相似文献   

10.
师范院校生物教育实习现状调查与思考   总被引:3,自引:0,他引:3  
陈忠 《生物学杂志》2005,22(3):54-56
通过对师范院校生物教育实习现状调查,了解基础教育改革深化背景下的生物教育实习模式、实习学校生物教育状况及生物教育实习生存在的问题和困惑等,并对高师院校课程设置、教育实习管理等问题进行反思,为高师院校生物教育实习和课程设计提供一些借鉴。  相似文献   

11.
Cellular metabolism is a very complex process. The biochemical pathways are fundamental structures of biology. These pathways possess a number of regeneration steps which facilitate energy shuttling on a massive scale. This facilitates the biochemical pathways to sustain the energy currency of the cells. This concept has been mimicked using electronic circuit components and it has been used to increase the efficiency of bio-energy generation. Six of the carbohydrate biochemical pathways have been chosen in which glycolysis is the principle pathway. All the six pathways are interrelated and coordinated in a complex manner. Mimic circuits have been designed for all the six biochemical pathways. The components of the metabolic pathways such as enzymes, cofactors etc., are substituted by appropriate electronic circuit components. Enzymes are related to the gain of transistors by the bond dissociation energies of enzyme-substrate molecules under consideration. Cofactors and coenzymes are represented by switches and capacitors respectively. Resistors are used for proper orientation of the circuits. The energy obtained from the current methods employed for the decomposition of organic matter is used to trigger the mimic circuits. A similar energy shuttle is observed in the mimic circuits and the percentage rise for each cycle of circuit functioning is found to be 78.90. The theoretical calculations have been made using a sample of domestic waste weighing 1.182 kg. The calculations arrived at finally speak of the efficiency of the novel methodology employed.  相似文献   

12.
杨静 《生命的化学》2020,40(2):284-287
"分子生物学实验"是分子生物学理论课配套的实验课。掌握分子生物学基本实验技术是生命科学对新时代人才发展的基本需求。上海科技大学通过整合教学资源与实验室资源,对传统本科生"分子生物学实验"的教学内容和体系进行调整,建立了一套基础实验与前沿实验相结合、验证性实验和自主设计性实验相结合的教学体系,为提高本科生"分子生物学实验"课程教学质量和培养综合型人才奠定了基础。  相似文献   

13.
“探究式学习”促使学生的学习方式和教师的教学方式发生深刻的变革.阐述了探究式学习、实验操作技能和探究式实验教学模式这三个概念的内涵.同时,对高中生物一个重要的验证性实验“叶绿体中色素的提取和分离”进行了改进,实施了探究式实验教学设计并进行了教学实践以及分析,旨在探讨如何培养学生的实验操作技能.由此可得出结论:开展探究式实验教学,既能通过规范的实验操作,培养学生的实验操作技能,又能培养学生的综合探究能力并树立实事求是的科学态度;利用随堂式的实验教学评价,能很好发挥探究式学习的成效.  相似文献   

14.
Computational biology and bioinformatics are gradually gaining grounds in Africa and other developing nations of the world. However, in these countries, some of the challenges of computational biology and bioinformatics education are inadequate infrastructures, and lack of readily-available complementary and motivational tools to support learning as well as research. This has lowered the morale of many promising undergraduates, postgraduates and researchers from aspiring to undertake future study in these fields. In this paper, we developed and described MACBenAbim (Multi-platform Mobile Application for Computational Biology and Bioinformatics), a flexible user-friendly tool to search for, define and describe the meanings of keyterms in computational biology and bioinformatics, thus expanding the frontiers of knowledge of the users. This tool also has the capability of achieving visualization of results on a mobile multi-platform context.

Availability

MACBenAbim is available from the authors for non-commercial purposes.  相似文献   

15.
Evolution is a complex subject that requires knowledge of basic biological concepts and the ability to connect them across multiple scales of time, space, and biological organization. Avida-ED is a digital evolution educational software environment designed for teaching and learning about evolution and the nature of science in undergraduate biology courses. This study describes our backward design approach to developing an instructional activity using Avida-ED for teaching and learning about evolution in a large-enrollment introductory biology course. Using multiple assessment instruments, we measured student knowledge and understanding of key principles of natural selection before and after instruction on evolution (including the Avida-ED activity). Assessment analysis revealed significant post-instruction learning gains, although certain evolutionary principles (most notably those including genetics concepts, such as the genetic origin of variation) remained particularly difficult for students, even after instruction. Students, however, demonstrated a good grasp of the genetic component of the evolutionary process in the context of a problem on Avida-ED. We propose that: (a) deep understanding of evolution requires complex systems thinking skills, such as connecting concepts across multiple levels of biological organization, and (b) well designed use of Avida-ED holds the potential to help learners build a meaningful and transferable understanding of the evolutionary process. An erratum to this article can be found at  相似文献   

16.
Despite holding to the essential distinction between mind and body, Descartes did not adopt a life-body dualism. Though humans are the only creatures which can reason, as they are the only creatures whose body is in an intimate union with a soul, they are not the only finite beings who are alive. In the present note, I attempt to determine Descartes' criteria for something to be 'living.' Though certain passages associate such a principle with the presence of a properly functioning heart, I show that there are important reasons for also understanding life in terms of a degree of complexity of design.  相似文献   

17.
I discuss the moral significance of artificial life within synthetic biology via a discussion of Douglas, Powell and Savulescu's paper 'Is the creation of artificial life morally significant’. I argue that the definitions of 'artificial life’ and of 'moral significance’ are too narrow. Douglas, Powell and Savulescu's definition of artificial life does not capture all core projects of synthetic biology or the ethical concerns that have been voiced, and their definition of moral significance fails to take into account the possibility that creating artificial life is conditionally acceptable. Finally, I show how several important objections to synthetic biology are plausibly understood as arguing that creating artificial life in a wide sense is only conditionally acceptable.  相似文献   

18.
植物生物学多媒体教学积件库的构建   总被引:3,自引:0,他引:3  
郝建华 《植物学通报》2004,21(1):121-127
植物生物学多媒体教学积件库由植物生物学教学资料库、教学单元库和在线测试与练习库等组成.其中的多媒体教学资料库是积件库的基础构成部分.多媒体教学资料可从互联网下载、文字和图片扫描、光盘采集和自己制作等多种途径进行构建.探讨了植物生物学积件库构建中遇到的一些问题和解决的对策.  相似文献   

19.
真核细胞翻译官始因子eIF-5A(eukaryotic initiation factor 5A)是迄今发现的惟一含有特殊氨基酸hypusine残基的蛋白质,其具体生物学功能仍不明确。为了推进对其功能的研究,拟从结构生物学入手,对其结构进行核磁共振(NMR)结构解析。利用GST融合蛋白原核表达系统,将eIF-5A进行原核表达,经过优化表达与纯化条件,得到了高产率与高纯度的可溶性eIF-5A用以进行NMR测试:经过!1H-^15N HSQC NMR实验,发现其适合应用NMR方法进行结构解析,从而为溶液中eIF-5A三维构象的研究奠定了基础.  相似文献   

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