英文教学课件-植物的世界(植物介绍、植物培育、食物制作)

TheWorldofPlants英文教学课件——植物的世界（植物介绍、植物培育、制作食物）

TheWorldofPlants英文教学课件——植物WorldofPlantsisdividedinto:A-IntroducingplantsB-Growingplants(Pollination,Fertilisation,Asexualreproduction)C-MakingfoodWorldofPlantsisdividedintPlants-thefirstlinkPlantsarethelinkbetweentheenergyinthesunbeingconvertedintoaformwhichanimalscaneatandgettheenergytosurvive…WorkbookActivityp54FoodwebsandplantsTheprocessbywhichplantsdothisiscalled:PhotosynthesisAlllivingthingsrespireallthetimetoreleaseenergyfromtheirfoodinaprocesscalled:RespirationPlants-thefirstlinkPlantsaPlantsurvivalPlantsmaketheirownfood,glucose,byphotosynthesis.Itonlyhappensduringthedaytimewhenthereislightavailable.Thishappensinplantcellscontainingthechemicalchlorophyll(green-coloured)whichtrapsthelightenergy.Theplantshavecapturedlightenergyandturneditintoastoreofchemicalenergy(glucose).RawmaterialsProductsLightenergycarbondioxide+water glucose+oxygenchlorophyllMoreontheusesforglucoseshortly…PlantsurvivalPlantsmaketheiIslightneededforphotosynthesis?Takeade-starchedgeraniumplant(24hindark).

Coverpartofaleafwithsometinfoil(thispreventslightgettingthrough).Leavetheplantinsunlightforafewhours.Testtheleafforstarch.IslightneededforphotosynthIscarbondioxideneededforphotosynthesis?Takeade-starchedgeraniumplantEncloseitinaplasticbagwithachemicalthatabsorbscarbondioxide.(e.g.sodalimeorsodiumhydroxidepellets).Leavetheplantinsunlightforacoupleofhours.Testtheleafforstarch.IscarbondioxideneededforpQuestions:Whichpartsoftheleafdoyouthinkwillgoblue-black?Whydopartsthatwerenotcoveredcontainstarch?Islightneededforphotosynthesis?WorkbookProblemSolvingp81MakingastarchprintQuestions:IslightneededforIscarbondioxideneededforphotosynthesis?Questions:Doestheleafcontainstarch?Why/whynot?

Hastheplantcarriedoutphotosynthesis?Whatwouldbeyourcontrolplant’sconditions?(Hint:acontrolplantshouldhaveeverythingitneedsforphotosynthesisincludingcarbondioxide).WorkbookProblemSolvingp76PlantsandgreenhousesCO2isconvertedintoglucosebyphotosynthesis.IscarbondioxideneededforpMans’usesofplantglucoseMans’usesofplantglucosePlants’usesofplantglucoseGlucoseUsedimmediatelytoprovideenergysourceforrespirationEnergyusedtoturnsugars,nitrates&othernutrientsintoaminoacidswhichbuildupproteinsTomakecellulose,themainstructuralmaterialincellwallsRawmaterialforgrowth,repairandreplacementofdamagedpartsEnergystored

as

starch(inleaves,seeds,rootsandtubers)Tomakefats&oils(energystoredinseeds)Energystoredassucrose(infruit)Plants’usesofplantglucoseGGlucosemoleculeWorkbookActivityp70ChangesincarbohydrateGlucosemoleculeWorkbookActivActivity

–TestingaplantforsugarPutapieceofrawonioninapestleandmortar.Grinditwithalittlesandand10cm3ofwater.FiltertheliquidintoatesttubeHeattheliquidwith10dropsBenedict’ssolutioninawaterbathWhatcolourchangewouldyouexpectifsugarwaspresent?b)Writeanexplanationofyourresults.Youneedtoknowtheplantexperimentsindetail,explainthedifferentsteps,andresults,ineachone.Activity

–TestingaplantfoActivity

-TestingaleafforstarchDipaleafintoboilingwaterforaboutaminute(tosoftenit).TurnofftheBunsenburner.Puttheleafintoatest-tubeofethanol(toremovechlorophyll).Standthetest-tubeinabeakerofhotwaterforabout10minutes.Washtheleafincoldwater.Spreadtheleafoutflatonapetridishandcoveritwithiodinesolution(testsforstarch).Iftheleafgoesblue-black, starchispresent.Activity

-TestingaleafforsActivity

-TestingaleafforchlorophyllRepeatthestarchtestbutthistimeuseavariegatedleaffromageraniumplant.Variegatedmeansthataplanthascolouredandwhitepartsonitsleaves.Dothegreenpartscontainchlorophyll?Dothewhitebits?Whichdoyouthinkwilltestpositiveforstarch?Activity

-TestingaleafforcFromlittleacornsdogreatoaksgrow…Wheredotheextra250kgcomefrom?Explainyouranswerasfullyandscientificallyasyoucan.Atreeisplantedinameadow.

After20yearsithasgrownintoabigtree,weighing250kgmorethanwhenitwasplanted.FromlittleacornsdogreatoaGasBalanceDuringtheday:Oxygen

releasedbyphotosynthesisisgreaterthantheamountofoxygenusedupinrespiration.CO2usedinphotosynthesisisgreaterthantheamountofCO2producedbyrespiration.glucose+oxygen

carbondioxide(CO2)+water

RespirationPhotosynthesiscarbondioxide+water glucose+oxygenallthetimedaylightonlyGasBalanceDuringtheday:gluc

Fillajarwithwater.Fillatesttubewithwatertooandcoverthetopasyouplaceitupsidedowninsidethejar.Takearunnerandfeeditupinsidethetesttube.LeaveindirectsunlightforafewhoursResult?Abubbleofoxygengasshouldformatthetopofthetesttubeasitphotosynthesises

SummaryofPhotosynthesisWorkbookActivityp64-65ElodeabubblerexptPlants’wasteproduct-oxygen-isessentialforanimallife.SummaryofPhotosynthesisWorkbQuickQuiz11.Whatdoesaplantneedforphotosynthesis?2.Whatdoesaleafproduceduringphotosynthesis?3.Whatischlorophyll?4.Howdotheleavesobtainwater?5.Howdoestheplantobtaincarbondioxide?6.List3usesoftheglucoseproducedbyphotosynthesis?7.Namethestorageformofcarbohydrateinaleaf.Carbondioxide,water,chlorophyll,light.Oxygen,glucoseAgreenpigmentwhichabsorbsthesun’senergyThroughtheroots(andxylemtubesbyosmosisFromtheair(throughstomata)Cellulose(structural),starch(storage),energyStarch.QuickQuiz11.WhatdoesaplaAleafintime

LibraryactivitySource:/plantbio/102/links.htmlReadthroughthefileandtakesomeshortnotestosummarisethelifeofaleaf/pp/books/online/leaf/alit_eng.pdfAleafintime

LibraryactivitLeaves…Leavesaretheorgansofphotosynthesisandmakeallthefoodforaplant.Wewilllookat:Outerlayers(top&bottom)Innerstructureincludingveins(itstransportsystem)Leaves…LeavesaretheorgansoInternalstructureCollectthehandout‘Leafstructure’andaddlabels/notes.mesophyllwaxycuticleInternalstructureCollecttheOuterlayer-uppersurface1.Thewaxy

cuticleisawaterprooflayerwhichcutsdownwaterlossbyevaporation.2.Theuppercellsoftheleafmakeuptheepidermis.Theyaretransparentsolightpassesstraightthroughthemintothenextlayerofcells…1.waxy2.Outerlayer-uppersurface1.TThepalisadelayercontainscellswithlotsofchloroplasts.Thespongylayer(spongymesophyll)containsroundedcellswithmanyairspacesallowingCO2tocirculateandreachthepalisadecells,whileO2leaves.Hencethisiswheremostphotosynthesisoccurs.Chloroplastscontainchlorophyllwhichisthechemicalwhichabsorbsthesun’slightenergy.mesophyllThepalisadelayercontainsceWorkbookActivitiesp66-67 Leafsurfaceandthicknessp67 Leaflayercards-matchingProblemSolvingp78Howmanystomata?p79Watercontentanddryweight.p85UseofcobaltchoridepaperBioviewers Box79TheleafofafloweringplantWorkbookActivitiesp66-67 LeaOuterlayer-bottomsurfaceLeafepidermiswithstomata-scanningelectronmicroscopeOnthelowersurfaceoftheleaftherearetinyporescalledstomata(singular-stoma)whichopenandclose.StomataletCO2diffusein.Watervapourandoxygen(O2)moveout.Outerlayer-bottomsurfaceLeaStomata-openStomatahaveguardcellssurroundingthemtocontroltheiropening&closing.Whenthereisplentyofwater(daytime)theguardcellsareturgidandcurved.Thisopensthestomataandwatercanescape.Workbookp62LeafsurfacesStomata-openStomatahaveguarStomata-closedWhenthereislittlewatertheguardcellsareflaccidandlesscurved.Thisclosesthestomataandkeepswater

intheleaf.Thishappensatnight.WorkbookActivity PSp63stomatabehaviour p82&83LeafbalanceStomata-closedWhenthereislGeneralstructureVastnetworkofveinssuppliesallpartsoftheplantwithessentialsubstancesStructuralsupportFlatleafbladeHaslargesurfaceareaAbsorbsasmuchsunlight&CO2aspossibleThinCO2,reachesinnercellseasilyStomataMostinlowersurfaceofleafGas&waterexchangeGeneralstructureVastnetworkLeafveinsLeafveins(androotsandstems)containthexylemandphloemtubesinvascularbundles.Theyrunthroughouttheplant,transportingvarioussubstancesupanddownthem.WorkbookProblemSolvingp80RingingaplantLeafveinsLeafveins(androotTransportsystemsusedfor?Plantsneedtoallow:

Gasestogetinandoutoftheleaves.

Waterandnutrientstomoveintotheplantfromthesoil.

Glucosemadeinphotosynthesistobecarriedtotherestoftheplant.Giantredwoodtreescarrywater&nutrientsover100mfromthesoilWorkbookActivityp61FoodtransportdiagramTransportsystemsusedfor?PlaRootsRootshavespecialisedcellscalledroothaircells,whicharelongandthinprovidingalargesurfaceareafortheuptakeofwaterandminerals.RootsRootshavespecialisedceIntotheroothaircellHOWDOESITHAPPEN?ThewaterinthesoilhasaweaksolutionofsaltsThecellsaphasamoreconcentratedsolutionWatermovesfromthesoilintotheroothairalongawaterconcentrationgradientWaterpassesfromthesoilintoroothairsbyosmosis

DEFINITIONOsmosisisthenetdiffusionofwateracrossapartiallypermeablemembrane,fromasolutionwithahighwaterconcentration(HWC)toonewithalowwaterconcentration(LWC).IntotheroothaircellHOWDOEOsmosisOsmosisOsmosisWhenwatermovesintoaplantcellbyosmosisitincreasesthepressureinsidethecell.Thecellwallsaresufficientlystrongtowithstandthepressure.Itisthispressurewhichkeepsthecellsrigid(maintainstheirturgor)andprovidessupport.Transpirationistheevaporationofwaterfromtheleavesofaplant.Thetranspirationstreamisthemovementofwaterupthexylem(roots-stem-leaves).OsmosisWhenwatermovesintoaWhy?

Soitisnotblown/knockedoverHow? Therootsspreadoutoveralargeareatocounterbalancethestructuresabovethesoil.Thisalsohelpsplantsfindwater.Functions1.AnchoringtheplantWhy? Soitisnotblown/knocManytinyhairsbranchoffthemainroot2.AbsorbessentialnutrientsWhy?

Totakeupsubstancestosurvive.How? Rootshavetinyhairsontheirsurfacewhichincreasestheirsurfaceareatomaximiseabsorption.ManytinyhairsbranchofftheAroothairshownunderamicroscopeRoothaircellRoothair3.AbsorbwaterWhy?

Waterisarawmaterialforphotosynthesis.How? Roothairsincreasesurfacearea.AroothairshownunderamicrTransportinFloweringPlantsInfloweringplantsthereareseparatetransportsystemsforwaterandnutrients.Substancesaretransportedinvascularbundlesmadeupofthexylemandthephloem.XylemTissueTransports

waterandminerals

upwardsfromtherootstothestemandleaves.TheXylemismadeofdeadcellsjoinedintohollowtubes.Theyhavethickstrongwallsmadeofligninwhichgivetheplantsupport.TransportinFloweringPlantsIPhloemtissuePhloemtissueCarriesnutrients,e.g.sugarsmadebyphotosynthesis,allroundtheplant.Thesugarsaretransportedallroundtheplantespeciallytogrowingregionsandthestorageorgans.Phloemcellsarealiveandaremadeof2typesofcells;sievetubesandcompanioncells.Sievecellendwallshaveholes(pores)inthem.Companioncellscontainthecellnuclei.PhloemtissuePhloemtissuePhloSugarcaneVascularbundles

arecomposedof

Xylem,Phloem

and

Fibreswhichsupportandprotectthexylemandphloem.LeafVeinsareVascularBundles.WorkbookActivityp72Structureofxylemandphloem.SugarcaneVascularbundlesareVascularbundlesWorkbookActivityp73LookingatxylemVascularBundlesinsugarcane.Left:cross-sectionBelow:detailofonebundleVascularbundlesWorkbookActivXylem&phloeminstemWorkbookActivityp60WatertransportinplantsBioviewers Box78ThestemofafloweringplantXylem&phloeminstemWorkbookPositionofvasculartissueinthestemepidermisxylemphloemThepositionsaredifferentinstemscomparedtoroots.Inastemtheyareroundtheoutside.PositionofvasculartissueinPositionofvasculartissuesintherootsepidermisxylemphloemWorkbookActivityp68-69Structurestem,rootInrootstheyarefoundinthecentre.PositionofvasculartissuesiWhatLimitsphotosynthesis?Forphotosynthesistohappenallthe“ingredients”needtobepresent.Ifthereareinadequateingredientsphotosynthesiswillstoporslowdown.Light+chlorophyllIngredientsCarbondioxide+water oxygen+glucoseThefactorthatisinshortestsupplywillbetheonethatlimitstherateofphotosynthesisandiscalleda“limiting

factor”.WhatLimitsphotosynthesis?FFactorslimitingphotosynthesisLowtemperatureShortageofCO2ShortageoflightLackofchlorophyll

Example:Aplanthasplentyofwater,carbondioxideandchlorophyll,butitisnight.Hence,photosynthesiscannottakeplaceduetolackoflight.Lightisthelimitingfactor.Oftenthissortofinformationisshowninagraph…FactorslimitingphotosynthesiRateLightintensityABCA

LightintensityislimitingtherateofreactionB

CO2islimitingtherateofreactionC

Thedifferencebetweenthelinesisduetodifferenttemperatures.p74Theeffectofincreasingcarbondioxidep75TheeffectofincreasingtemperatureWorkbookActivityRateLightintensityABCALightQuickQuiz22.Give2structuralfeaturesofaleafthatmakeitagooddesignforphotosynthesis.3.Whydoyouthinkthatthepalisadecellsarenearthesurfaceoftheleaf?4.Namethecellsthatsurroundthestomatalopenings.5.Thespongymesophyllcellsarelooselyarranged.Explainthesignificanceofthis.6.Which3factorslimittherateofphotosynthesis?1.Howisglucosecarriedfromtheleavestoeverypartoftheplant?Transportedinphl