浙科版“细胞的增殖（第1课时）”的教学设计

1教材分析 本节的内容主要涉及有丝分裂。在介绍了细胞周期的概念和分裂后,教材安排了观察活动,存此基础上,教材重点阐述了动、植物有丝分裂的过程和意义。最后通过观察活动,巩同所学的有丝分裂知识,体会人们研究细胞有丝分裂过程的方法和手段,培养熟练制作植物细胞有丝分裂临时装片的技能。     

“基因指导蛋白质的合成”（第1课时）的教学设计

1教学内容本节课是人教版《必修2》第4章“基因的表达”的第1节内容。集中讲述的是基因指导蛋白质合成的内容。课程标准中与本节教学相对应的要求是：概述遗传信息的转录。“概述”是理解水平的要求．即要求学生能够把握知识的内在逻辑联系,能够与已有的知识建立联系,进行解释、     

“生物对环境的适应和影响（第2课时）”的教学设计

本课选自人教版7年级上册,第1单元“生物和生物圈”的第2章第3节。本册教材从内容框架上是要突出人与生物圈的关系,本节课所属的第2章“生物圈是所有生物的家”就是站在生物圈的高度,论述生物与环境之间是相互影响、相互依存的统一整体。本课“生物对环境的适应和影响”则是在前一节课“环境对生物的影响”的基础上考虑生物与环境之间的关系．实际上是从一个问题的2个方面对生物与环境的关系辩证地进行分析。     

“遗传信息的表达——RNA和蛋白质的合成”的教学设计（第1课时）

1教材分析 本节为高中生物学必修2《遗传与进化》（浙江科学技术出版社）第3章第4节的第1课时,重点内容是概述遗传信息的转录、翻译过程。整节课阐明转录是遗传信息由DNA传递到RNA上的过程。其场所主要在细胞核,产物是RNA;翻译是以mRNA为模板合成多肽链的过程,其场所是在核糖体上,此过程需要tRNA作为运载工具。     

“植物细胞工程”的教学设计

1教学背景分析1．1内容分析本节课是人教版生物学教材选修3“现代生物科技专题”专题2“细胞工程”2．1“植物细胞工程”。本内容包括“植物细胞工程的基本技术”和“植物细胞工程的实际应用”2部分。分2课时,本文讨论第1课时。     

“有机物的分解利用—呼吸作用”一节教学设计

学生是学习的主体 ,在启发引导学生自已探索、省悟知识的过程中培养学生的思维能力和创新精神 ,是课堂教学的重要目标。在本节课中 ,我主要通过让学生参与新知识的学习和探索过程 ,充分调动学生感观和思维积极活动 ,从而激发学生的学习兴趣 ,掌握学习知识的方法 ,培养创造性思维能力。1　课前准备种子呼吸时吸收氧的实验装置 1套 ,种子呼吸时释放二氧化碳实验装置 1套 ,澄清石灰水 ,玻璃管若干支 ,试管若干支 ,装有煮熟种子、萌发种子和干燥种子的暖瓶各 1个 ,温度计 3支 ,洋葱根、叶呼吸装置各 1套。2　教学过程2 .1　情景激凝1)呈现一幅生…     

“染色体变异”（第1课时）的教学设计

本节课教学尝试采用建构主义学习理论设计,力求体现新课改理念。通过创设情境导入、提纲引领自学、概念生成与转换及建构新知识、原理应用与“STS”教育、知识再现与应用提升等教学环节达成教学目标,尤其是运用图表解读、设问与讨论、引导探究、整理归纳、磁性染色体放大模型的摆放等教学方式帮助学生理解、学习相关概念。     

“生态系统的能量流动”(第1课时)的教学设计

以《普通高中生物课程标准》的基本理念和建构主义学习理论为指导思想,教师利用教材中的“问题探讨”为主线贯穿整节课,引导学生借助模型建构的方法自主对“生态系统的能量流动”进行系统分析,在建构中实现行为与思维的统一,有效激发学生学习生物科学的兴趣,提升科学探究能力.     

新教材第三章“生物的新陈代谢”内容分析及教学建议

1　新教材内容选择的价值取向原教材强调了以学科为中心 ,形成了良好的知识框架及经验背景 ,比较重视理论的传授 ,但忽视了与社会的实际联系 ;比较注重学生学得知识 ,而对如何获得知识的方法和过程缺乏引导。新教材内容的价值取向定位在 :综合考虑了学科体系 ,体现了生物学科的基础性、发展性和时代性 ;考虑了社会的需求 ;兼顾了学生认知过程的发展。因此 ,新教材在努力构建“面向现代化、面向世界、面向未来”的同时 ,面对学生、面对生活、面对社会 ,设置了有关知识方面、态度观念方面和能力方面的课程目标 :1 1　知识方面1 1 1　体现基…     

Evolution and phylogenetic utility of the period gene in Lepidoptera

Evolution and phylogenetic utility of the period gene are explored through sequence analysis of a relatively conserved 909-bp fragment in 26 lepidopteran species. Taxa range from tribes to superfamilies, primarily within the putative clade Macrolepidotera plus near outgroups, and include both strongly established and problematic groupings. Their divergence dates probably range from the late Cretaceous through much of the Tertiary. Comparisons within the same set of closely related species show that amino acid substitutions in period occur 4.9 and 44 times as frequently as they do in two other nuclear genes--dopa decarboxylase and elongation factor-1 alpha, respectively. In contrast, rates of observed synonymous substitution are within 60% of each other for these three genes. Synonymous changes in period approach saturation by the family level, whereas nonsynonymous and amino acid divergences across the Macrolepidoptera are less than half the maximal values reported for this gene. Phylogenetic analyses of period strongly supported groupings at the family level and below. In contrast to previous analyses at this level with other nuclear genes, much of the information lies in nonsynonymous change. Relationships up to the superfamily level were recovered with decreasing effectiveness, and little, if any, signal was apparent regarding relationships among superfamilies. This could reflect rapid radiation of the superfamilies, however, rather than saturation in the period locus; thus, period, in combination with other genes, remains a plausible candidate for approaching the difficult problems of lepidopteran family and superfamily relationships.      

Prolactin and luteinizing hormone (LH) release throughout the postpartum period in the suckled first-calf beef cow

A study was performed to examine the release patterns of prolactin and LH of young beef cows with one (single calf) or two calves (double calf) throughout the postpartum interval. The effect on prolactin release of intramuscular and intra-carotid administration of lergotrile and intra-carotid administration of L-dopa was also examined. In approximately 50% and 65% of the cases, no prolactin release could be detected after the beginning of or during the suckling stimulus in cows with one or two calves respectively. LH plasma concentrations remained constant throughout the experiment in all animals. The chosen intramuscular lergotrile treatment lowered plasma prolactin concentrations to baseline levels but had no effect on the length of the postpartum interval. No effect on prolactin release was observed by the given intra-carotid treatments of both lergotrile and L-dopa. First postpartum estrus was observed on days 67 and 88 in the single and double calf cows respectively. The number of suckling periods did not change during the postpartum period but their duration decreased during the same period. These results demonstrate that in at least half of the cases the suckling stimulus does not cause a release of prolactin from the pituitary in the young beef cow. Also, the inhibitory effect of suckling on the resumption of ovarian cyclic function postpartum appears to be of a quantitative nature and mediated by a factor other than prolactin.     

Contextual alignment of biological sequences (Extended abstract)

We present a model of contextual alignment of biological sequences. It is an extension of the classical alignment, in which we assume that the cost of a substitution depends on the surrounding symbols. In this model the cost of transforming one sequence into another depends on the order of editing operations. We present efficient algorithms for calculating this cost, as well as reconstructing (the representation of) all the orders of operations which yield this optimal cost. A precise characterization of the families of linear orders which can emerge this way is given.     

Contextual modulation of visuomotor associations in bumble-bees (Bombus terrestris)

We performed the following experiment to investigate whether contextual cues can prevent interference during the acquisition of potentially competing visuomotor associations. In the bumble-bee (Bombus terrestris). Bees discriminated between horizontally and vertically orientated gratings of black and white stripes in order to reach a feeder and between different diagonally orientated gratings to gain access to their nest. Once bees were well trained on these two tasks, the discrimination task at the nest was changed so that bees had to distinguish between horizontal and vertical gratings at both sites. Whereas they still approached the horizontal grating to reach food, they now had to approach a vertical grating in order to return to their nest. The new task was learnt rapidly. Errors at the feeder did not increase during or after the acquisition of this potentially competing behaviour at the nest entrance. For a brief period during acquisition, bees showed some hesitation at the feeder and hovered for slightly longer before choosing between horizontals and verticals. After acquisition was complete, bees showed a slight increase in their preference for verticals over a more ambiguous stimulus of an array of dots. These findings are consistent with the hypothesis that different contextual signals are associated with approaching the nest or approaching the feeder, and that these contextual signals facilitate learnt associations between orientation detectors and motor commands.     

Temporal and Contextual Patterns of Killer Whale (Orcinus orca) Call Type Production

Fish-eating killer whales Orcinus orca in the northeastern Pacific live in highly stable matrifocal social groups called pods. Each pod produces a repertoire of seven or more stereotyped call types. We compared the relative production of call types of free-ranging killer whale pods over time and between social contexts. The relative production of call types by each pod during directional travel was distinct over a 27-yr period; however, both temporal stability and pod distinctiveness were strongly influenced by a subset of dominant call types within the repertoire of each pod. Some call types within the repertoires contain biphonation (two overlapping independently modulated tones) and have a higher estimated active space than call types containing just one tone. In multi-pod aggregations the relative production of the dominant call types of each pod decreased and the relative production of a subset of call types that are rarely recorded from single-pod groupings increased. The majority of these contained biphonation. The data suggest a distinction between a subset of dominant call types that may function to identify the pod and a subset of less common call types including several call types containing biphonation that are more commonly produced during inter-pod affiliations.     

Evolution and phylogenetic utility of CAD (rudimentary) among Mesozoic-aged Eremoneuran Diptera (Insecta)

We sequenced nearly the entire carbomoylphosphate synthase (CPS) domain of CAD, or rudimentary, (ca. 4 kb) from 29 species of flies representing all major clades within Eremoneura, or higher flies, and several orthorrhaphous brachyceran outgroups. We compared these sequences with orthologs from Anopheles gambiae and Drosophila melanogaster to assess structure, compositional bias, and phylogenetic utility. CAD is large (6.6+ kb), complex (comprised of three major and myriad minor functional domains) and relatively free of introns, extreme nucleotide bias (except third codon positions), and large hypervariable regions. The CPS domain possesses moderate levels of nonsynonymous divergence among taxa of intermediate evolutionary age and conveys considerable phylogenetic signal. Phylogenetic analysis of CPS sequences under varying methods and assumptions resulted in well-resolved, strongly supported trees concordant with many traditional ideas about higher dipteran phylogeny and with prior inferences from 28S rDNA. The most robustly supported major eremoneuran clades were Cyclorrhapha, Platypezoidea, Eumuscomorpha, Empidoidea, Atelestidae, Empidoidea exclusive of Atelestidae, Hybotidae s.l., Microphoridae+Dolichopodidae, and Empididae s. str. Because CAD is ubiquitous, apparently single copy (at least within holometabolous insects), readily obtained from several insect orders using primers described herein, and exhibits considerable phylogenetic utility, it should have wide applicability in insect molecular systematics.     

Epidemiology of coeliac disease in children in one Croatian county: the cumulative incidence over ten-year period and the way of clinical presentation (Part I)

Coeliac disease is a permanent intolerance to gluten, producing small-intestinal lesions. Its incidence in European countries varies from 1:400 to 1:2000, while there are no such epidemiological data for Croatia. Therefore, we investigated the incidence of coeliac disease for ten-year period in one well-defined region. Also, data concerning age at diagnosis and symptoms at the disease onset were collected. The cumulative incidence was 1.9:1000 life-births. The disease presented typically in more than 60% of cases. In 65% of patients, symptoms appeared during the first 2 years of life, while, when diagnosed, 45% were below 2 years. Also, it was shown that coeliac disease presented significantly later in children diagnosed during the last five years (p < 0.05). In conclusion, coeliac disease in Croatia is more frequent than previously suspected. It presents early, mostly with classical symptoms, although a tendency towards later ages of diagnosis was observed during the last few years.     

Resumption of gonadotrophin release during the post-partum period in suckling and non-suckling ewes

The post-partum secretion of LH, FSH and prolactin was monitored in 15 suckling and 6 non-suckling Préalpes du Sud ewes lambing during the breeding season by measuring plasma hormone concentrations daily at 6-h intervals and also weekly at 20-min intervals for 6 h from parturition to resumption of regular cyclic ovarian activity. There was a constant phenomenon in the resumption of normal patterns of FSH and LH secretion: there was a rise in FSH values culminating on average on Day 4 post partum and returning subsequently to values observed during the oestrous cycle, and concurrently an increase in the frequency and amplitude of LH pulses more progressive in suckling than in non-suckling ewes which led to an elevation of LH mean concentrations and occurrence of an LH surge. Since neither the FSH secretory pattern nor FSH mean values differed between suckling and non-suckling ewes, the results suggested that LH pulsatile pattern was a major limiting factor for the resumption of normal oestrous cycles. Before regular oestrous cycles resumed other changes in preovulatory LH surges also occurred: (i) they increased in duration and probably in amplitude; (ii) they were preceded by an acceleration in LH pulse frequency and a large decrease in FSH values as in normal cyclic ewes; and (iii) at least in non-suckling ewes they occurred concurrently with a prolactin surge.