收藏 分销(赏)

第二真核微生物的形态-结构和功能.pptx

上传人:精*** 文档编号:4339713 上传时间:2024-09-08 格式:PPTX 页数:94 大小:1.38MB
下载 相关 举报
第二真核微生物的形态-结构和功能.pptx_第1页
第1页 / 共94页
第二真核微生物的形态-结构和功能.pptx_第2页
第2页 / 共94页
第二真核微生物的形态-结构和功能.pptx_第3页
第3页 / 共94页
第二真核微生物的形态-结构和功能.pptx_第4页
第4页 / 共94页
第二真核微生物的形态-结构和功能.pptx_第5页
第5页 / 共94页
点击查看更多>>
资源描述

1、Definition:eukaryotic cells are compartmentalized by membranes .The cell contains several different types of membrane bou nd organelle in which different biochemical and physiological processes can occur in a regulated way.Membranes also transport information,metabolic intermediats and endproducts f

2、rom the site of biosynthesis to the site of use.Eukaryotes is a big group of living organisms made up of eukaryotic cells.with membrane bound nucleus and several organelles such as mitochondrion etal.and divided by mitosis.真核生真核生物是一大类细胞核具有核膜,能进行有丝分裂,细胞质中存在线粒体或同时存在叶绿体等多物是一大类细胞核具有核膜,能进行有丝分裂,细胞质中存在线粒体或

3、同时存在叶绿体等多种细胞器的生物种细胞器的生物.eukaryotic microorganisms is a group of Microorganisms that made up of eukaryotic cells include Fungi、microalgae()、()、and protozoa真核细胞真核细胞真核生物真核生物 真核微生物真核微生物peroxisomesmitochondrioncytosolchloroplastSmooth endoplasmic reticulumStructure of a typical plant cellCytosol细胞液Plasma

4、 membraneSecretory vesiclesStructure of a typical animal cellmembraneCell wall mitochondrionVesicals(泡囊泡囊)Dictyosomes(分散高尔基体)Hyphal structuresEndoplasmic reticlumribosomesmembranevacuoleCell wallmitochondrionNucleus Endoplasmic reticulumYeast structuresYeast structures 真核微生物主要包括真核微生物主要包括菌物界菌物界(Mycet

5、alia或广义的或广义的“Fungi”)中的真菌中的真菌(Eumycota或狭义的或狭义的“Fungi”,即,即True Fungi)、粘菌粘菌(Myxomycota或或Fungilike Protozoa)、假菌假菌(Chromista或或Pseudofungi),植物界植物界(Plantae)中的显微藻类中的显微藻类(Algae)和和动物界动物界(Animalia)中的原生动物中的原生动物(Protozoa)Major groups of eukaryotic microorganisms 真核微生物的主要类群真核微生物的主要类群 植物界植物界 (plantae):显微藻类):显微藻类 a

6、lgae 动物界(动物界(animalia):原生动物):原生动物 protozoa 真核微生物真核微生物 黏菌黏菌myxomycota 假菌假菌pseudofungi 菌物界(菌物界(mycetalia)单细胞真菌单细胞真菌unicellular fungi 真菌真菌 eumycota 丝状真菌丝状真菌filamentous 大型子实体大型子实体 蕈菌蕈菌 mushroomMajor groups of eukaryotic microorganisms Eukaryotic microorganisms“菌物界菌物界这个名词是我国学者裘维蕃等于这个名词是我国学者裘维蕃等于19901990年

7、提出的,并已年提出的,并已得到学术界的一定支持,得到学术界的一定支持,这是指与动物界、植物界相并列的一大群无叶这是指与动物界、植物界相并列的一大群无叶绿素、依靠细胞表面吸收有机养料、细胞壁一绿素、依靠细胞表面吸收有机养料、细胞壁一般含有几丁质的真核微生物。一般包括真菌、般含有几丁质的真核微生物。一般包括真菌、粘菌和假菌粘菌和假菌(卵菌等卵菌等)3)3类。类。真菌是最重要的真核微生物,故是本章的重点,它们真菌是最重要的真核微生物,故是本章的重点,它们的特点是:的特点是:无叶绿素,不能进行光合作用;无叶绿素,不能进行光合作用;一般具有发达的菌丝体;一般具有发达的菌丝体;细胞壁多数含几丁质;细胞壁多

8、数含几丁质;营养方式为异养吸收型;营养方式为异养吸收型;以产生大量无性和以产生大量无性和(或或)有性孢子的方式进行繁殖;有性孢子的方式进行繁殖;陆生性较强陆生性较强Fungi are filamentous,nonphotosynthetic,eukaryotic microorganisms that have a heterotrophic nutrition.Their basic cellular unit is described as a hypha.This is a tubular cell which is surrounded by a rigid,chitincontai

9、ning cell wall.The hypha extends by tip growth,and multiplies by branching,creating a fine network called a mycelium.Hyphae contain nuclei,mitochondria,ribosomes,Golgi and membranebound vesicles within a plasmamembrane bound cytoplasm.The subcellular structures are supported and organized by microtu

10、bules and endoplasmic reticulum.The cytoplasmic contents of the hypha tend to be concentrated towards the growing tip.Older parts of the hypha are heavily vacuolated and may be separated from the younger areas by cross walls called septae.Not all fungi are multicellular,some are unicellular and are

11、termed yeasts.These grow by binary fission or budding,creating new individuals from the parent cell.Mould(Mold)nDefinition Mold are filamentous,nonphotosynthetic,eukaryotic microorganisms that have a heterotrophic nutrition(filamentous fungi)。Morphology and structureHypha and mycelium菌丝与菌丝体 lower fu

12、nginon-septate myceliums higher fungiseptate mycelium with elaborate、perforate septa The hypha extends by tip growth,and multiplies by branching,creating a fine network called a mycelium.(plural mycelia)Mycelia can be divided into vegatative mycelium and aerial mycelium(营养菌丝体和气生菌丝体)Basic unithypha(p

13、l。hyphae)This is a tubular cell which is surrounded by a rigid,chitin-containing cell wall.Hyphae contain nuclei,mitochondria,ribosomes,Golgi and membrane-bound vesicles within a plasma-membrane bound cytoplasm membraneCell wall mitochondrionVesicals Dictyosomes(分散高尔基体)Hyphal structuresSpecialized m

14、orphology of vegetative mycelium营养菌丝体的特化形态营养菌丝体的特化形态nRhizoid 假根Rhizopus nStolon 匍匐菌丝Mucorales、Rhizopus nHaustorium 吸器nAdhesive cell 附着胞nAdhesive branch 附着枝nSclerotium 菌核nRhizomorph,funiculus菌索n ring and net 菌环和菌网1)假根(rhizoid)是Rhizopus(根霉属)等低等真菌匍匐菌丝与固体基质接触处分化出来的根状结构,具有固着和吸取养料等功能 (2)匍匐菌丝匍匐菌丝(stolon)又称

15、匍匐枝。毛霉目又称匍匐枝。毛霉目(Mueorales)真菌在固体基真菌在固体基质上常形成与表面平行、具有延伸功能的菌丝,称匍匐菌丝。最典型质上常形成与表面平行、具有延伸功能的菌丝,称匍匐菌丝。最典型的可在的可在Rhizopus中见:在固体基质表面的营养菌丝分化为匍匐菌丝,中见:在固体基质表面的营养菌丝分化为匍匐菌丝,在其上每隔一段距离在其上每隔一段距离可长出伸人基质的假根可长出伸人基质的假根 根霉的形态和构造和伸向空间的孢囊梗,根霉的形态和构造和伸向空间的孢囊梗,随着匍匐菌丝的延伸,不断形成新的假根和孢囊梗,这类真菌会随基随着匍匐菌丝的延伸,不断形成新的假根和孢囊梗,这类真菌会随基质的存在而向

16、四处快速蔓延,根本就不会形成像在其他真菌中常见的质的存在而向四处快速蔓延,根本就不会形成像在其他真菌中常见的那样有固定大小和形态的菌落。那样有固定大小和形态的菌落。sporangium(3)吸器吸器(haustorium)由几类专性寄生的真菌如锈菌目由几类专性寄生的真菌如锈菌目(Uredinales)、霜霉目、霜霉目(Peronosporales)和白粉菌目和白粉菌目(Erysiphales)等的一些种所产生。吸器是一种只在宿主细等的一些种所产生。吸器是一种只在宿主细胞间隙间蔓延的营养菌丝上分化出来的短枝,它可侵入细胞间隙间蔓延的营养菌丝上分化出来的短枝,它可侵入细胞内形成指状、球状或丝状的构

17、造,用以吸取宿主细胞内胞内形成指状、球状或丝状的构造,用以吸取宿主细胞内的养料而不使其致死。的养料而不使其致死。(4)附着胞附着胞(adhesive cell)许多寄生于植物的真菌在其芽管许多寄生于植物的真菌在其芽管或老菌丝顶端会发产或老菌丝顶端会发产 膨大,分泌粘状物,借以牢固地粘附在膨大,分泌粘状物,借以牢固地粘附在宿主的表面,此即附着胞。在其上再形成针状感染菌丝,以宿主的表面,此即附着胞。在其上再形成针状感染菌丝,以侵入宿主的角质表皮而吸取养料。侵入宿主的角质表皮而吸取养料。(5)附着枝附着枝(adhesive branch)若干寄生真菌由菌丝细胞生出若干寄生真菌由菌丝细胞生出12个细胞

18、的短枝,将菌丝附着于宿主体上,个细胞的短枝,将菌丝附着于宿主体上,(6)菌核()菌核(sclerotium)是一种形状、大小不一的是一种形状、大小不一的休眠菌丝组织,在不良外界条件下:可保存数年生命休眠菌丝组织,在不良外界条件下:可保存数年生命力。菌核形状有大有小,大的如茯苓力。菌核形状有大有小,大的如茯苓(大如小孩头大如小孩头),小的如油菜菌核小的如油菜菌核(形如鼠粪)。菌核的外层色深、坚形如鼠粪)。菌核的外层色深、坚硬、内层疏松,大多呈白色。硬、内层疏松,大多呈白色。(7)菌索()一般由伞菌等产生,为白色根状菌丝)菌索()一般由伞菌等产生,为白色根状菌丝组织,功能为促进菌体蔓延和抵御不良环

19、境。通常组织,功能为促进菌体蔓延和抵御不良环境。通常可在腐朽的树皮下和地下发现。可在腐朽的树皮下和地下发现。(8)菌环菌环(loop)和菌网和菌网(net)捕虫菌目捕虫菌目(zoopasdes)和一些半知菌的菌丝常会分化成圈环或网状的特化和一些半知菌的菌丝常会分化成圈环或网状的特化菌丝组织,用以捕捉线虫或其他微小动物,然后进菌丝组织,用以捕捉线虫或其他微小动物,然后进一步从这类环或网上生出菌丝侵入线虫等体内,吸一步从这类环或网上生出菌丝侵入线虫等体内,吸收养料收养料(9)子实体()子实体(fruiting body,sporocarp,fructification)Colonial growt

20、hHyphal tip growth allows fungi to extend into new regions from a point source or inoculum(接种物接种物).Older parts of the hyphae are often emptied of contents as the cytoplasm is taken forwards with the growing tip.(老的菌丝通常缺乏内含物,因为细胞质流向生长点老的菌丝通常缺乏内含物,因为细胞质流向生长点)This creates the radiating colonial pattern

21、 seen on agar plates,in ringworm infections of skin and fairy rings in grass lawns.Only hyphal tips contribute to extension growth.However older hyphae can grow aerially or differentiate to produce sporing structures(只(只有菌丝顶端对延伸生长起作用,而老菌丝可以进行气生生长或分化出产孢有菌丝顶端对延伸生长起作用,而老菌丝可以进行气生生长或分化出产孢子的结构)子的结构)Myceli

22、um in agarAgar Surface myceliumKinetics of growth Fungal growth in a given medium follows the growth phases of lag,acceleration,exponential,linear,retardation,stationary and decline(延迟期、加速期、指数期、直线期、减速期、稳定期、衰亡期)(延迟期、加速期、指数期、直线期、减速期、稳定期、衰亡期).Exponential growth occurs only for a brief period as hyphae

23、branches initiated,and then the new hypha extends at a linear rate into uncolonized regions of substrate.Life cycles All fungi are characterized by having a period of vegetative growth where their biomass increases.The length of time and the amount of biomass needed before sporulation can occur vari

24、es.Almost all fungi reproduce by the production of spores,but a few have lost all sporing structures and are referred to as mycelia sterilia(不育不育菌丝体菌丝体).Different types of spore are produced in different parts of the life cycle.Reproduction in fungiAll fungi undergo a period of vegetative growth whe

25、re their mycelium exploits a substrate.This stage is followed by asexual and sexual reproduction.There are two conflicting requirements fungi have for their spores.Spores must allow fungi to spread,but they must also allow them to survive adverse conditions.These requirements are met by different ty

26、pes of spores.Small,light spores are carried furthest from parent mycelium in air and these are the dispersal spores(释放型孢子)(释放型孢子).They are usually the products of asexual sporulation,the sporangiospores and the conidiospores,and so spread genetically identical individuals as widely as possible.Gene

27、tic diversity is maintained by sexual reproduction,and the spore products are often large resting spores(休眠孢子)(休眠孢子)that withstand adverse conditions but remain close to their site of formation.Spores therefore vary greatly is size,shape and ornamentation,and this variation reflects specialization o

28、f purpose.Fungal spores:spores allow fungi to spread,to maintain genetic diversity and to survive adverse conditionsReproduction in fungi spore discharge:Spores that have a dispersal function can be released from their parent mycelium by active or passive mechanisms.As many spores are wind dispersed

29、,they are produced in dry friable masses which are passively discharged by wind.Other spores are passively discharged by water droplets splashing spores away from parent mycelium.Spores may be discharged from parent mycelium by passive or active means.Passive mechanisms include using wind and water

30、as dispersants;active mechanisms use explosive principles.Fungal spore discharge Spores in the atmosphere(airborne fungal spores)can be carried great distances。Their presence in the air can have impact on human health as they can cause allergic rhinitus(hay fever)and asthma。Many plant diseases that

31、cause great economic losses are air borne。can affect human,animal and plant health.They can cause allergies and spread plant disease.Air sporaFungi reproduce by the formation of sexual or asexual spores Asexual reproductionfission ArthrosporeBudding blastosporeOther asexual spore Zoospore Chlamydosp

32、ore Sporangiospore conidiospora Sexual reproduction Oospore Zygospore Ascospore Basidiospore节孢子节孢子(arthrospore)某些真菌生长到一定阶某些真菌生长到一定阶段,菌丝中间形成许多段,菌丝中间形成许多隔膜,接着从隔膜处断隔膜,接着从隔膜处断裂成许多竹节似的无性裂成许多竹节似的无性孢子,称为节孢子,也孢子,称为节孢子,也称为粉孢子。最典型的称为粉孢子。最典型的例于是白地霉例于是白地霉(Geotrichumcandidum).arthrosporeBlastospore(芽孢子芽孢子)这和酵母菌的

33、出芽这和酵母菌的出芽一样,它是由母细胞生一样,它是由母细胞生芽而形成的。当芽长到芽而形成的。当芽长到正常大小时,脱离母细正常大小时,脱离母细胞,或仍连在母细胞上。胞,或仍连在母细胞上。如玉蜀黍黑粉菌如玉蜀黍黑粉菌(Ustilago maydis)能产生芽孢子。某些毛能产生芽孢子。某些毛霉或根霉在液体培养基霉或根霉在液体培养基中形成的被称为酵母型中形成的被称为酵母型细胞,也属芽孢子。细胞,也属芽孢子。又称厚壁孢子或厚膜孢子。某又称厚壁孢子或厚膜孢子。某些真菌生长到些真菌生长到定阶段,在菌丝的定阶段,在菌丝的顶端或中间有部分细胞的细胞质密顶端或中间有部分细胞的细胞质密集在一起,变圆,然后在其四周生

34、集在一起,变圆,然后在其四周生出厚壁,或原细胞壁加厚,形成圆出厚壁,或原细胞壁加厚,形成圆形、纺锤形的无性休眠体,来抵抗形、纺锤形的无性休眠体,来抵抗外界不良的环境条件。例如总状外界不良的环境条件。例如总状毛霉毛霉(Mucor racemosus)往往在菌往往在菌丝中间形成许多厚垣孢子丝中间形成许多厚垣孢子schlamydospore(厚垣孢子)(厚垣孢子)无性繁殖产生的孢子在孢子囊无性繁殖产生的孢子在孢子囊(Sporange)(Sporange)内内,孢子囊一般孢子囊一般生在气生菌丝的顶端或生在孢囊梗生在气生菌丝的顶端或生在孢囊梗(sporangiophore)(sporangiophore

35、)的顶端。的顶端。在形成孢子囊前,首先有多核的原生质密集于此处,使其膨在形成孢子囊前,首先有多核的原生质密集于此处,使其膨大,并在下方生出横隔,形成圆形的囊状物,然后其中原生大,并在下方生出横隔,形成圆形的囊状物,然后其中原生质体割裂成许多小块,每质体割裂成许多小块,每块发育成为块发育成为个孢子囊孢子。因个孢子囊孢子。因而每一而每一个孢子囊所含有的孢子的数个孢子囊所含有的孢子的数般都相当多。般都相当多。就孢子囊孢子而言就孢子囊孢子而言,般有二类般有二类,一种具有一种具有根或根或2323根根鞭毛,能够游动,所以称游动孢子鞭毛,能够游动,所以称游动孢子(zoospore)(zoospore)。例如

36、腐霉。例如腐霉(即即thium)thium)。另一种无鞭毛,不能游动,又称静止担于。另一种无鞭毛,不能游动,又称静止担于。sporangiospore(孢子囊孢子孢子囊孢子)游动孢子游动孢子 conidium(分生孢子分生孢子)分生孢子的形成方法分生孢子的形成方法 其形成方式有两种,一种是在分生孢子梗的顶端突其形成方式有两种,一种是在分生孢子梗的顶端突出,发育成第一个孢子。梗再伸长形成第二个孢子,如出,发育成第一个孢子。梗再伸长形成第二个孢子,如此重复形成一串孢子。这样形成的分生孢子,顶端的最此重复形成一串孢子。这样形成的分生孢子,顶端的最老。曲霉属和青霉届的分生孢子形成,即属于此类型。老。曲

37、霉属和青霉届的分生孢子形成,即属于此类型。另一种是在第另一种是在第个分生孢子形成时,柄的个分生孢子形成时,柄的长度已达到最高,由第一个分生孢子顶端生长长度已达到最高,由第一个分生孢子顶端生长出第二个分生孢子,如此重复形成一串孢子。出第二个分生孢子,如此重复形成一串孢子。这样形成的分生孢子,下部的最老。如枝孢霉这样形成的分生孢子,下部的最老。如枝孢霉属属(Cladosporium)(Cladosporium)的分生孢子形成即属于此类的分生孢子形成即属于此类型。型。Plastic kitchen cutting board surface-rod bacteria in a smooth matr

38、ix;filamentous bacteria(丝状菌丝状菌)-smooth oval cells;fungal hyphae(真菌菌丝真菌菌丝)with textured spores(结构孢子结构孢子)(x 2,270)conidiumZoospore(游动孢子)(游动孢子)Asexual spore,usually produced by fungi living in water.Motile zoospores in motile sporangia differentiated from swelled hyphal tips have a single posterior fla

39、gellum。The structure of the flagellum is 9+2,some has two flagella.霉菌的有性繁殖是经过不霉菌的有性繁殖是经过不同性别的细胞结合同性别的细胞结合(质配和质配和核配核配)后,产生一定形态的后,产生一定形态的孢子来实现的,这种孢子孢子来实现的,这种孢子称为有性孢子。繁殖过程称为有性孢子。繁殖过程可分为三个阶段:第可分为三个阶段:第个个阶段为质配;第二个阶段为质配;第二个阶段为核配,产生二倍体阶段为核配,产生二倍体的核;第三个阶段是减数的核;第三个阶段是减数分裂,恢复核的单倍体状分裂,恢复核的单倍体状态。大多数真菌菌体是单态。大多数真

40、菌菌体是单倍体的。有性孢子通常有倍体的。有性孢子通常有下列几种:下列几种:Sexual reproduction 菌丝分为雄器菌丝分为雄器(antheridium)(antheridium)和藏卵器和藏卵器(oogonium)(oogonium)。藏卵器中。藏卵器中有一个或数个卵球有一个或数个卵球(oosphere)(oosphere)。当雄器和。当雄器和藏卵器相配时,雄器中藏卵器相配时,雄器中细胞质与细胞核,通过细胞质与细胞核,通过受精管而进入藏卵器,受精管而进入藏卵器,与卵球结合形成卵孢子。与卵球结合形成卵孢子。图所示是德巴利腐霉的图所示是德巴利腐霉的卵孢子的形成。卵孢子的形成。oospo

41、re(卵孢子卵孢子)(b b)同宗结合)同宗结合(a a)异宗结合)异宗结合根霉的接合孢子根霉的接合孢子Zygospore(接合孢子)(接合孢子)ascospore(子囊孢子)(子囊孢子)形成子囊孢子是子囊菌的主要特征。子囊中孢子数目通常为18个,或为2n。典型的子囊中有8个孢子。大多数霉菌的子囊是包裹在子囊果(ascocarp)中。子囊果有三种类型 子囊壳 perithecium 子囊盘apothecium 闭囊壳cleistothecium Sexual reproduction in this group occurs after somatic fusion of different

42、matingtype mycelia.A transient diploid phase is rapidly followed by the formation of ascospores within sacshaped asci differentiated from modified hyphal tips.In the initial stages of ascal development hooked hyphal tips form,called croziers(产囊丝钩)(产囊丝钩)or shepherds crooks(牧羊杖)(牧羊杖)because of their s

43、hape.They have distinctive septae at their base which insure that two different matingtype nuclei are maintained in the terminal cell.Formation of the septae is coordinated with nuclear division.In yeasts all these events occur within one cell,after fusion of two matingtype cells,the whole cell bein

44、g converted into an ascus.The formation of ascosporesSexual reproduction in the ascomycetes In more complex Ascomycetes many asci form together,creating a fertile tissue called a hymenium(叫子实层的能育组织)(叫子实层的能育组织).In some groups the hymeniumcan be supported or even enclosed by large amounts of vegetativ

45、e mycelium.The whole structure is called a fruit body or sporocarp(子囊果)(子囊果)and is used as a major taxonomic feature.They can become large enough to be seen with the naked eye.Flaskshaped sexual reproductive bodies are called perithecia,cupshaped bodies are called apothecia and closed bodies are cal

46、led cleistothecia.These structures have evolved to protect the asci in spore dispersal,but the hymenium itself is unafected by the presence of water。The formation of sporocarp and its formsCupshaped apotheciumFlaskshaped peritheciumClosed cleistotheciumAsci Asci Ascus containing ascosporesBasidiomyc

47、ete fungi rarely reproduce asexually.Sexual reproduction is by the formation of basidiospores on the gills or pores of large fruit bodies.This group of fungi are characterized by the most complex and large structures found in the fungi.They are also distinctive in that they very rarely produce asexu

48、al spores.Much of the life cycle is spent as vegetative mycelium,exploiting complex substrates.A preliminary requisite for the onset of sexual reproduction is the acquisition of two mating types of nuclei by the fusion of compatible hyphae.Single representatives of the two matingtype nuclei are held

49、 within every hyphal compartment for extended periods of time.This is termed a dikaryotic state(双核期)(双核期),and its maintenance requires elaborate septum formation during growth and nuclear division.Basidiospore Onset of sexualspore formation is triggered by environmental conditions and begins with th

50、e formation of a fruit body primordium(子实体原基)(子实体原基).Dikaryotic mycelium(双核菌丝体)(双核菌丝体)expands and differentiates to form the large fruit bodies we recognize as mushrooms and toadstools(毒(毒蕈)蕈).Diploid formation and meiosis occur within a modified hyphal tip called a basidium。Basidium formation 核融合核融

展开阅读全文
相似文档                                   自信AI助手自信AI助手
猜你喜欢                                   自信AI导航自信AI导航
搜索标签

当前位置:首页 > 教育专区 > 其他

移动网页_全站_页脚广告1

关于我们      便捷服务       自信AI       AI导航        获赠5币

©2010-2024 宁波自信网络信息技术有限公司  版权所有

客服电话:4008-655-100  投诉/维权电话:4009-655-100

gongan.png浙公网安备33021202000488号   

icp.png浙ICP备2021020529号-1  |  浙B2-20240490  

关注我们 :gzh.png    weibo.png    LOFTER.png 

客服