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1.
小动物浸制标本简易制法   总被引:1,自引:0,他引:1  
小动物浸制标本简易制法学习动物学,制作标本是十分重要的教学环节。利用废物品制作动物标本,既经济又实用,具有推广的价值。本文介绍一种制作小型动物浸制标本的简易方法;(1)处理把采集到的小动物(长小于2.scm、直径小于1.5cm),如家蚕、蜘蛛、蚜虫、...  相似文献   

2.
秦岭天然锐齿栎林群落区系研究   总被引:1,自引:1,他引:0  
锐齿栎林是秦岭林区的主要森林类型之一。通过对秦岭天然锐齿栎林群落的野外调查,报道了组成该群落的植物种类183种,隶属于60科,131属,并在此基础上对该群落区系特点作了较为详细的分析。分析表明:1.该群落区系具有明显的温带性质。2.该群落区系是奠基在秦岭古老植物区系的基础上,通过种间竞争、群落演替形成的。3.锐齿栎本身不是一个古老的类群,其出现的时间不会早于上新世。  相似文献   

3.
通过样地调查、树干解析及直径分析法,对神农架地区广泛分布的米心水青冈( Fagusengleriana Seem .) 林和锐齿槲栎( Quercus aliena var. acuteserrata Maxim .) 林受压和释压历史及更新策略进行了研究。结果表明:米心水青冈直径生长表现为5 种模式,而锐齿槲栎只表现为2 种模式。(85.9±6.9)% 的米心水青冈有过受压过程,平均受压2 .1±0 .8 次,平均受压时间为(47 ±24.1) a,最长受压时间73 a,平均释压次数为1 .6 ±0 .7 次,平均释压时间为(23 ±21.5) a,而60.83% 的锐齿槲栎都均有1 次受压,平均受压时间为(19 ±14) a,受压后没有表现出释压过程。结合高生长和径向生长,认为米心水青冈是耐荫树种,它的更新策略主要是在林下形成苗性萌枝,在有林窗形成时释压生长进入乔木层;而锐齿槲栎是不耐荫树种,其更新策略主要是通过产生大量种子,当有大的林窗时,幼苗在林窗内生长逐步进入乔木层  相似文献   

4.
常用的温(热)型血管注射剂多为动物明胶,虽能在血管中凝结,但其加热程度不易掌握,注射、洗涤麻烦;而冷型注射剂,如甘油、淀粉、墨汁等,注射虽方便,却不能在血管中凝结,能在血管中凝固硬化的如树胶、赛潞路等,又只能做腐蚀标本。本注射剂具有上面2者的优点:既能在室温下以不同浓度注射,}能使其在血管中及时凝结(仅是凝结,不是硬化、固化,不影响血管弹性)。透明血管标本的制作似以国外SPalteholz氏法为最著名,其透明液为冬绿油[白珠树油(oaultheriaoil)、邻羟苯(甲)酸甲酯〕(D”一1.ssl~1.s38)和苯甲酸菜酯(…  相似文献   

5.
秦岭锐齿栎林种群生态位特征研究   总被引:47,自引:4,他引:43  
基于秦岭林区锐齿栎群落31块400m^2的样地调查数据,以物种的重要值为生态位计算的资源状态指标,应用Levins、Hurlbert公式和Pianka公式对该林区锐齿栎群落24种主要乔木和29种灌木进行了生态位宽度和生态位重叠计算与分析.结果表明,该群落中主要优势种群的生态位宽度较大,乔木层的主要优势种群锐齿栎、华山松、漆树、山杨、油松等的Levins、Hurlbert生态位宽度值分别为3.695、1.695、1.325、O.840、0.702和0.036、0.299、0.568、1.721、2.701,灌木层的主要优势种群榛子、美丽胡枝子、鞘柄菝葜等的Levins、Hurlbert生态位宽度值分别为1.833、1.466、0.984和0.111、0.300、0.594.生态位宽度较大的物种对资源利用能力较强,与其它种群间的生态位重叠一般较大;对相似环境要求的物种间生态位重叠较大.  相似文献   

6.
玉米(zeamaxs)常常作为遗传学实验材料,用来验证遗传的分离规律和自由组合规律。然而不易保存,少则一二年,多则二三年玉米穗就会因菌腐或虫蛀而损坏。既造成经济损失,又影响了遗传学的实验教学工作。为了有效地解决上述问题,我经过多次试验,终于摸索出制作“永久性杂交玉米穗标本”的方法和技术。工材料与方法1.回材料来源当年采收的单因子杂交种、双因子杂交种、测交种、杂种优势等不同类型的玉米稳共计140个。1·2材料处理1·2·回阴凉风干因为玉米果实有后熟作用,收获后仍含有大量的水溶性糖,通过后熟随籽粒的成熟而逐渐转化…  相似文献   

7.
花背蟾蜍生态浸制标本制作方法新探一般动物生态浸制标本的制作.由于整形时不作特殊的技术处理,只是用5%~7%的甲醛溶液直接浸泡处死,经简单整形处理.浸于7%~10%的甲醛溶液固定封存即可;而对处死和固定时所用时间的长短不作具体说明和要求。在花背赡殊生态...  相似文献   

8.
林祁 《生物学通报》1997,32(4):40-41
一株植物或者植物体的一部分经过压制干燥以后称为腊(读音xi)叶标本。腊叶标本经过装订可以收藏在标本柜中长期保存,为生产、科研和教学服务。目前,我国各地中学已经普遍开展自制腊叶标本,为生物学教学眼务。由于各所学校采用的装订方法和用具不同,使得标本装订后质量各异。为了提高腊叶标本的装订质量,在此介绍2种较流行的腊叶标本装订法。1胶粘装订法该方法所需用具较多,装订速度快,是国际上较流行的腊叶标本装订法。1.工装订用具台纸垫衬标本用,标本装订在台纸上。台纸要求坚韧,通常用白卡纸制作,大小为8开,约39x28cm。标…  相似文献   

9.
四川九寨沟和甘南叶蜂二新种(膜翅目:叶蜂科)   总被引:1,自引:0,他引:1  
记述四川九寨沟和甘肃南部山地分布的2个叶蜂新种:石氏钩瓣叶蜂Macrophya shii Wei,sp.nov.和黑刺齿唇叶蜂Rhogogaster nigrospina Wei,sp.nov.。模式标本保存于中南林学院昆虫标本室。  相似文献   

10.
中、小型土壤动物标本的采集与制备1中、小型土壤动物标本的采集体长大于2mm的大型土壤动物一般采用手拣法,体长0.2~2mm的中、小型土壤动物的采集用干漏斗引诱法(Tullgren)和湿漏斗引诱法(Baermann)最有效。于漏斗引诱法用一个金属圆筒(...  相似文献   

11.
通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.  相似文献   

12.
Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m−2 s−1. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to Pfr.  相似文献   

13.
14.
真菌类遗传学分析的知识结构教学   总被引:5,自引:2,他引:3  
罗桂花 《遗传》2002,24(3):349-350
本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.  相似文献   

15.
The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.  相似文献   

16.
A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.  相似文献   

17.
18.
龙胆科药用植物化学成分的研究现状   总被引:16,自引:0,他引:16  
龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。  相似文献   

19.
Seven strains of aerobic carbon monoxide-oxidizing bacteria (carboxydebacteria) when growing on CO as sole source of carbon and energy had doubling times which ranged from 12–42 h. The activity profiles obtained after discontinuous sucrose density gradient centrifugation indicated that the CO-oxidizing enzymes are soluble and the hydrogenases are membrane-bound in all strains examined. The CO-oxidizing enzymes of Pseudomonas carboxydohydrogena, Pseudomonas carboxydoflava, Comamonas compransoris, and the so far unidentified strains OM2, OM3, and OM4 had a molecular weight of 230,000; that of Achromobacter carboxydus amounted to 170,000. The molecular weights of the CO-oxidizing and H2-oxidizing enzymes turned out to be identical. The cell sonicates were shown to catalyze the oxidation of both CO and H2 with methylene blue, thionine, phenazine methosulfate, toluylene blue, dichlorophenolindophenol, cytochrome c or ferricyanide as electron acceptors. Methyl viologen, benzyl viologen, FAD+, FMN+, and NAD(P)+ were not reduced. The spectrum of electron acceptors was identical for all strains tested. Neither free formate, hydrogen nor oxygen gas were involved in the CO-oxidation reaction. Methylene blue was reduced by CO at a 1:1 molar ratio. The results indicate that CO-oxidation by carboxydobacteria is catalyzed by identical or similar enzymes and that the reaction obeys the equation CO+H2OCO2+2H++2e- as previously shown for Pseudomonas carboxydovorans.Dedicated to Otto Kandler remembering almost three decades of enjoyable cooperation  相似文献   

20.
Since the introduction of the concepts of allostery about four decades ago, much advancement has been made in elucidating the structure-function correlation in allostery. However, there are still a number of issues that remain unresolved. In this review we used mammalian pyruvate kinase (PK) as a model system to understand the role of protein dynamics in modulating cooperativity. PK has a triosephosphate isomerase (TIM)(α/β)8 barrel structural motif. PK is an ideal system to address basic questions regarding regulatory mechanisms about this common (α/β)8 structural motif. The simplest model accounting for all of the solution thermodynamic and kinetic data on ligand-enzyme interactions involves two conformational states, inactive ET and active ER. These conformational states are represented by domain movements. Further studies provide the first evidence for a differential effect of ligand binding on the dynamics of the structural elements, not major secondary structural changes. These data are consistent with our model that allosteric regulation of PK is the consequence of perturbation of the distribution of an ensemble of states in which the inactive ET and active ER represent the two extreme end states. Sequence differences and ligands can modulate the distribution of states leading to alterations of functions. The future work includes: defining the network of functionally connected residues; elucidating the chemical principles governing the sequence differences which affect functions; and probing the nature of mutations on the stability of the secondary structural elements, which in turn modulate allostery.  相似文献   

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