Chapter 3 Cell Structure第3章细胞结构 (52)课件

Chapter3-CellStructure1Chapter3-CellStructure1I.Lookingatcells A.MicroscopesRevealcellstructure 1.Mostcellsaretoosmalltoseewiththenakedeye,atypicalhumanbodycellismanytimessmallerthangrainsand.

2.RobertHookefirstsawthecellandexplainedwhathesawas,“alotoflittleboxes.”

2I.Lookingatcells A.Micro33 2.AntonvanLeeuwenhoekdiscovered“animalcules,”todayweknowthemassinglecelledorganisms

4 2.AntonvanLeeuwenhoekdi B.Measuringthesizesofcellstructure 1.Measurementstakenbyscientistsareexpressedinmetricunits. 2.

Scientiststhroughouttheworldusethemetricsystem.5 B.Measuringthesizesofce 3.Theofficialname-InternationalSystemofMeasurement-SI.

4.SIisadecimalsystem,soallrelationshipsarebasedonpowersoften.

5.LookandKNOWtable3.1

6 3.Theofficialname-Intern77 C.Characteristicsofmicroscopes

1.Inalightmicroscope,lightpassesthroughoneormorelensestoproduceanenlargedimageofaspecimen.

8 C.Characteristicsofmicros99 2.Anelectronmicroscopeformsanimageofaspecimenusingabeamofelectronsratherthanlight.

10 2.Anelectronmicroscopefo 3.Magnificationistheabilitytomakeanimageappearlargerthanitsactualsize.

4.Resolutionisameasureoftheclarityofanimage.

5.Bothmagnificationandresolutionisneededtoviewmicroscopicorganisms.11 3.Magnificationistheabil D.Microscopeshavedifferentusesandlimitations

1.Lightmicroscopesthatusetwolensesarecalledcompoundlightmicroscopes.

2.Compoundmicroscopescanhaveatotalmagnificationupto2,000X

12 D.Microscopeshavedifferen 3.Electronmicroscopescanmagnifyanimageupto200,000Xandtheycanbeusedtostudyeventhesmalleststructuresinsidecellsoronthecellsurface.

4.Intransmissionelectronmicroscopestheelectronbeamisdirectedataverythinsliceofaspecimenstainedwithmetalions.13 3.Electronmicroscopescan 5.Scanningelectronmicroscopestheelectronbeamisfocusonaspecimencoatedwithaverythinglayerofmetal.

6.Thescanningtunnelingmicroscopeusesaneedle-likeprobetomeasuredifferencesinvoltagecausedbyelectronsthatleak,ortunnelfromthesurfaceoftheobjectsbeingviewed.

14 5.ScanningelectronmicroscII.CellFeatures A.SchwannandVirchowformthecelltheorywhichhasthreeparts:

1.

Alllivingthingsaremadeupofoneormorecells.

2.

Cellsarethebasicunitsofstructureandfunctioninorganisms.

3.

Allcellsarisefromexistingcells.

15II.CellFeatures A.Schwann B.Cellsmustbesmall 1.Theyaresmallbuttheycontaineverythingthatisneeded.16 B.Cellsmustbesmall161717 C.Commonfeaturesofcell 1.Cellssharecommonstructurefeatures,includinganouterboundarycalledthecellmembrane.Thecellmembraneenclosesthecellandseparatesthecell.

2.Cytoplasmisthejellylikesubstanceofthecell.

18 C.Commonfeaturesofcell181919 3.Insidethecytoplasmaremanystructures,oftensuspendedinasystemofmicroscopicfiberscalledcytoskeleton.

20 3.Insidethecytoplasmare

4.Ribosomesmakeprotein

21

21 B.Prokaryotesdonotcontaininternalcompartments

1.

Aprokaryoteisasingle-celledorganismthatlacksanucleusandotherinternalcompartments.

2.

Modernprokaryotesarecalledbacteria.

22 B.Prokaryotesdonotcontai2323 3.Thecytoplasmofabacterialcellincludeseverythinginsidethecellmembrane.

4.Bacterialcellshaveacellwallsurroundingthecellmembranethatprovidesstructureandsupport.

5.Manybacteriahaveflagella,whicharelong,threadlikestructuresthatallowthebacteriatomove.24 3.Thecytoplasmofabacter2525 D.Eukaryoticcellsareorganized

1.Thefirstcellswithinternalcompartmentsappeared1.5billionyearsago.

2.Aeukaryoteisanorganismwhosecellshaveanucleus.26 D.Eukaryoticcellsareorga 3.Thenucleusisaninternalcompartmentthathousesthecell’sDNA.

4.Anorganelleisastructurethatcarriesoutspecificactivitiesinthecell.

5.Shorthairlikestructuresiscalledcilia.

6.Seefigure3.8toseeanEukaryoticcell.

27 3.Thenucleusisaninternal2828 F.ThestructureandFunctionofcellmembranesarecloselyrelated.

1.Theselectivepermeabilityofthecellmembraneiscausedmainlybyaphospholipid.

2.Inacellmembrane,thephospholipidsarearrangedinadoublelayercalledalipidbelayed.

3.

Seefigure3.9

29 F.ThestructureandFunctio3030 4.Variousproteinsarelocatedinthelipidbilayerofacellmembrane.

5.Cellmembranescontaindifferenttypesofproteins,eachplaysavitalroleinthelifeofacell.31 4.VariousproteinsarelocaIII.CellOrganelles A.TheNucleusDirectsCellActivitiesandStoresDNA

1.

MostfunctionsofaEukaryoticcellareacontrolledbythecell’snucleus.

2.

Adoublemembranecalledthenuclearenvelope,alsocalledthenuclearmembrane,surroundsthenucleus.

3.

ThehereditaryinformationofaEukaryoticcelliscodedinthecell’sDNA,whichisstoredinthenucleus.32III.CellOrganelles A.The3333 B.Aninternalmembranesystemprocessesproteins

1.

Unlikeprokaryoticcells,Eukaryoticcellshaveasystemofinternalmembranesthatplayanessentialroleintheprocessingofproteins.

34 B.Aninternalmembranesyst C.Productionofproteins

1.

Theendoplasmicreticulum(ER)movesproteinsandothersubstancesthroughthecell.Itactslikeahighway.

2.

ThereisroughandsmoothER.RoughERhasribosomesattachedtoitandsmoothERdoesnot.

35 C.Productionofproteins35 3.Aseachproteinismade,itcrossestheERmembraneandenterstheER.TheportionoftheERthatcontainsthecompletedproteinthenpinchesofftoformavesicle.

4.Avesicleisasmall,membrane-boundsacthattransportssubstancesincell.36 3.Aseachproteinismade,iSmoothER37SmoothER37RoughER38RoughER38 D.Packaginganddistributingofproteins

1.TheGolgiapparatusisasetofflattened,membrane-boundsacsthatservesasthepackaginganddistributingcenterofthecell.ItactsliketheUPSofthecell.

2.Thecellalsohaslysosomes.Theyarevesicles,whichcontaindigestiveenzymes.Theyeatthegarbageofthecells.“Suicidebags.”

39 D.PackaginganddistributinGolgi40Golgi40Lysosomes41Lysosomes41 E.StepsoftheGolgi

1.

RibosomesmakeproteinsandhopontheERforaride.

2.

TheERtakesthemtotheGolgi.

3.

TheGolgirepackagestheproteinsintowhatthecellneeds.

42 E.StepsoftheGolgi42 4.Golgispitsoutthenewvesselsandtheygowheretheyareneeded.

5.Lysosomesgoaroundandeatuptheoldordamagedvessels.43 4.Golgispitsoutthenewv4444 F.MitochondriaProducesATP

1.

NearlyallEukaryoticcellscontainmanymitochondria.

2.

MitochondrionmakesATP(energy)forthecell.“Powerhouseofthecell.”

45 F.MitochondriaProducesATP4646

G.Plantcellscontainstructuresthatanimalcellslack

1.

Thecellmembraneofaplantcellissurroundedbyacellwall.(AnimalcellsDONOThaveacellwall)

2.

Thecellwallhelpstosupportandmaintainthecell’sshape,protectsthecellfromdamage.

3.

ItDOESNOTpreventinthingsinouroutofthecellthisisthecellmembranesjob.47 G.Plantcellscontainstruc 4.Plantcellscontainoneormorechloroplasts.

5.Chloroplastsareorganellesthatuselightenergytomakefood.

6.Chloroplastsmakechlorophyll.

7.Muchoftheplantcell’svolumeistakenupbyalarge;membraneboundspacecalledthecentralvacuole.48 4.Plantcellscontainoneo49495050

8.Vacuolesarefoundinbothplantandanimalcells.

9.Onlyplantcellscontainacentralvacuole.

10.Thecentralvacuolestoreswaterandmanycontainmanysubstancesincludingions,nutrientsandwastes.

11.Whenthecentralvacuoleisfull,itpressesthecytoplasmagainstthecellwall,makingthecellrigidwhichmakestheplantstandupright.

51 8.VacuolesarefoundinbotTheEnd52TheEnd52Chapter3-CellStructure53Chapter3-CellStructure1I.Lookingatcells A.MicroscopesRevealcellstructure 1.Mostcellsaretoosmalltoseewiththenakedeye,atypicalhumanbodycellismanytimessmallerthangrainsand.

2.RobertHookefirstsawthecellandexplainedwhathesawas,“alotoflittleboxes.”

54I.Lookingatcells A.Micro553 2.AntonvanLeeuwenhoekdiscovered“animalcules,”todayweknowthemassinglecelledorganisms

56 2.AntonvanLeeuwenhoekdi B.Measuringthesizesofcellstructure 1.Measurementstakenbyscientistsareexpressedinmetricunits. 2.

Scientiststhroughouttheworldusethemetricsystem.57 B.Measuringthesizesofce 3.Theofficialname-InternationalSystemofMeasurement-SI.

4.SIisadecimalsystem,soallrelationshipsarebasedonpowersoften.

5.LookandKNOWtable3.1

58 3.Theofficialname-Intern597 C.Characteristicsofmicroscopes

1.Inalightmicroscope,lightpassesthroughoneormorelensestoproduceanenlargedimageofaspecimen.

60 C.Characteristicsofmicros619 2.Anelectronmicroscopeformsanimageofaspecimenusingabeamofelectronsratherthanlight.

62 2.Anelectronmicroscopefo 3.Magnificationistheabilitytomakeanimageappearlargerthanitsactualsize.

4.Resolutionisameasureoftheclarityofanimage.

5.Bothmagnificationandresolutionisneededtoviewmicroscopicorganisms.63 3.Magnificationistheabil D.Microscopeshavedifferentusesandlimitations

1.Lightmicroscopesthatusetwolensesarecalledcompoundlightmicroscopes.

2.Compoundmicroscopescanhaveatotalmagnificationupto2,000X

64 D.Microscopeshavedifferen 3.Electronmicroscopescanmagnifyanimageupto200,000Xandtheycanbeusedtostudyeventhesmalleststructuresinsidecellsoronthecellsurface.

4.Intransmissionelectronmicroscopestheelectronbeamisdirectedataverythinsliceofaspecimenstainedwithmetalions.65 3.Electronmicroscopescan 5.Scanningelectronmicroscopestheelectronbeamisfocusonaspecimencoatedwithaverythinglayerofmetal.

6.Thescanningtunnelingmicroscopeusesaneedle-likeprobetomeasuredifferencesinvoltagecausedbyelectronsthatleak,ortunnelfromthesurfaceoftheobjectsbeingviewed.

66 5.ScanningelectronmicroscII.CellFeatures A.SchwannandVirchowformthecelltheorywhichhasthreeparts:

1.

Alllivingthingsaremadeupofoneormorecells.

2.

Cellsarethebasicunitsofstructureandfunctioninorganisms.

3.

Allcellsarisefromexistingcells.

67II.CellFeatures A.Schwann B.Cellsmustbesmall 1.Theyaresmallbuttheycontaineverythingthatisneeded.68 B.Cellsmustbesmall166917 C.Commonfeaturesofcell 1.Cellssharecommonstructurefeatures,includinganouterboundarycalledthecellmembrane.Thecellmembraneenclosesthecellandseparatesthecell.

2.Cytoplasmisthejellylikesubstanceofthecell.

70 C.Commonfeaturesofcell187119 3.Insidethecytoplasmaremanystructures,oftensuspendedinasystemofmicroscopicfiberscalledcytoskeleton.

72 3.Insidethecytoplasmare

4.Ribosomesmakeprotein

73

21 B.Prokaryotesdonotcontaininternalcompartments

1.

Aprokaryoteisasingle-celledorganismthatlacksanucleusandotherinternalcompartments.

2.

Modernprokaryotesarecalledbacteria.

74 B.Prokaryotesdonotcontai7523 3.Thecytoplasmofabacterialcellincludeseverythinginsidethecellmembrane.

4.Bacterialcellshaveacellwallsurroundingthecellmembranethatprovidesstructureandsupport.

5.Manybacteriahaveflagella,whicharelong,threadlikestructuresthatallowthebacteriatomove.76 3.Thecytoplasmofabacter7725 D.Eukaryoticcellsareorganized

1.Thefirstcellswithinternalcompartmentsappeared1.5billionyearsago.

2.Aeukaryoteisanorganismwhosecellshaveanucleus.78 D.Eukaryoticcellsareorga 3.Thenucleusisaninternalcompartmentthathousesthecell’sDNA.

4.Anorganelleisastructurethatcarriesoutspecificactivitiesinthecell.

5.Shorthairlikestructuresiscalledcilia.

6.Seefigure3.8toseeanEukaryoticcell.

79 3.Thenucleusisaninternal8028 F.ThestructureandFunctionofcellmembranesarecloselyrelated.

1.Theselectivepermeabilityofthecellmembraneiscausedmainlybyaphospholipid.

2.Inacellmembrane,thephospholipidsarearrangedinadoublelayercalledalipidbelayed.

3.

Seefigure3.9

81 F.ThestructureandFunctio8230 4.Variousproteinsarelocatedinthelipidbilayerofacellmembrane.

5.Cellmembranescontaindifferenttypesofproteins,eachplaysavitalroleinthelifeofacell.83 4.VariousproteinsarelocaIII.CellOrganelles A.TheNucleusDirectsCellActivitiesandStoresDNA

1.

MostfunctionsofaEukaryoticcellareacontrolledbythecell’snucleus.

2.

Adoublemembranecalledthenuclearenvelope,alsocalledthenuclearmembrane,surroundsthenucleus.

3.

ThehereditaryinformationofaEukaryoticcelliscodedinthecell’sDNA,whichisstoredinthenucleus.84III.CellOrganelles A.The8533 B.Aninternalmembranesystemprocessesproteins

1.

Unlikeprokaryoticcells,Eukaryoticcellshaveasystemofinternalmembranesthatplayanessentialroleintheprocessingofproteins.

86 B.Aninternalmembranesyst C.Productionofproteins

1.

Theendoplasmicreticulum(ER)movesproteinsandothersubstancesthroughthecell.Itactslikeahighway.

2.

ThereisroughandsmoothER.RoughERhasribosomesattachedtoitandsmoothERdoesnot.

87 C.Productionofproteins35 3.Aseachproteinismade,itcrossestheERmembraneandenterstheER.TheportionoftheERthatcontainsthecompletedproteinthenpinchesofftoformavesicle.

4.Avesicleisasmall,membrane-boundsacthattransportssubstancesincell.88 3.Aseachproteinismade,iSmoothER89SmoothER37RoughER90RoughER38 D.Packaginganddistributingofproteins

1.TheGolgiapparatusisasetofflattened,membrane-boundsacsthatservesasthepackaginganddistributingcenterofthecell.ItactsliketheUPSofthecell.

2.Thecellalsohaslysosomes.Theyarevesicles,whichcontaindigestiveenzymes.Theyeatthegarbageofthecells.“Suicidebags.”

91 D.PackaginganddistributinGolgi92Golgi40Lysosomes93Lysosomes41 E.StepsoftheGolgi

1.

RibosomesmakeproteinsandhopontheERforaride.