Plant reproduction Y10 - Mr Lovat...
Transcript of Plant reproduction Y10 - Mr Lovat...
-
DRM Biology Y10DRM Biology Y10 11
PlantPlant reproductionreproduction
��TheThe plantplant cyclecycle
��Asexual Asexual reproductionreproduction
��Sexual Sexual reproductionreproduction::��TheThe flowerflower
��PollinationPollination
��FruitFruit andand seedseed formationformation
��SeedSeed dispersaldispersal
��SeedSeed germinationgermination
-
DRM Biology Y10DRM Biology Y10 22
TheThe plantplant cyclecycle in non in non
floweringflowering plantsplants
-
DRM Biology Y10DRM Biology Y10 33
TheThe plantplant cyclecycle in in floweringflowering
plantsplants
-
DRM Biology Y10DRM Biology Y10 44
Asexual Asexual reproductionreproduction in in
plantsplants
�� By By stolonsstolons andand runnersrunners (as in (as in grassesgrasses))
�� By By sporesspores (as in (as in fernsferns andand mossesmosses))
�� By By tuberstubers (as in (as in potatoespotatoes))
�� By By bulbsbulbs (as in (as in onionsonions))
�� By By graftsgrafts ((usedused mostlymostly in in gardeninggardening))
In In thisthis case, case, allall individualsindividuals are are geneticallygenetically identicalidentical toto thethe parentparent plantplant..
-
DRM Biology Y10DRM Biology Y10 55
ExamplesExamples ofof asexual asexual
reproductionreproduction in in plantsplants
Fern spores
stolons
tubers bulbs
-
DRM Biology Y10DRM Biology Y10 66
Sexual Sexual reproductionreproduction in in
floweringflowering plantsplants
�� PlantsPlants produce produce reproductivereproductive organsorgans calledcalledflowersflowers. .
�� TheseThese flowersflowers havehave specialisedspecialised structuresstructureswhichwhich are are eithereither femalefemale oror malemale..
�� Sexual Sexual cellscells calledcalled gametesgametes are made in are made in thethereproductivereproductive organsorgans. .
�� TheThe gametesgametes fusefuse in a in a processprocess calledcalledfertilisationfertilisation. .
�� FollowingFollowing fertilisationfertilisation, , fruitsfruits andand seedsseeds developdevelopfromfrom partsparts ofof thethe formerformer flowerflower..
-
DRM Biology Y10DRM Biology Y10 77
PartsParts ofof thethe flowerflower
-
DRM Biology Y10DRM Biology Y10 88
PartsParts ofof thethe flowerflower
petal
stigma
style
ovaryovule
anther
filament
sepal
-
DRM Biology Y10DRM Biology Y10 99
PollinationPollination
ItIt isis thethe transfertransfer ofofthethe pollenpollen graingrainfromfrom thethe antheranther totothethe stigmastigma..
ThisThis can be done in can be done in thethe samesame flowerflower((selfself--pollinationpollination)) ororin in differentdifferent flowersflowers(cross(cross--pollinationpollination).).
-
DRM Biology Y10DRM Biology Y10 1010
WindWind--pollinatedpollinated flowersflowers
�� FlowersFlowers are are usuallyusually veryverysmallsmall, , withwith no no petalspetals andandno no scentscent..
�� AnthersAnthers andand stigmasstigmas are are exposedexposed toto thethe windwind..
�� StigmasStigmas are are hairyhairy ororfeatheryfeathery toto traptrap thethe pollenpollengrainsgrains blownblown by by thethe windwind..
�� PollenPollen grainsgrains are are smoothsmooth, , lightlight andand veryvery smallsmall toto be be easilyeasily carriedcarried by by thethe windwind..
�� ExampleExample: : grassesgrasses
stigma
anther
-
DRM Biology Y10DRM Biology Y10 1111
InsectInsect--pollinatedpollinated flowersflowers
�� HaveHave bigbig, , colourfulcolourfulpetalspetals toto attractattractinsectsinsects..
�� HaveHave nectarnectar andand//ororscentscent toto attractattractinsectsinsects ororhummingbirdshummingbirds..
�� StamenStamen andand stigmasstigmasinsideinside thethe corollacorolla..
�� PollenPollen grainsgrains are are bigbig, , andand withwith hookshooks totoattachattach toto insectinsect’’sslegslegs..
-
DRM Biology Y10DRM Biology Y10 1212
FertilisationFertilisation
TheThe pollenpollen graingrain growsgrowsa a pollenpollen tubetube whichwhichwillwill carrycarry thethe nucleusnucleusofof thethe malemale gametegamete totothethe ovule, ovule, toto meetmeet thethefemalefemale eggegg cellcell..
FertilisationFertilisation isis thethefusionfusion ofof thethe nucleusnucleusofof thethe malemale gametegametewithwith thethe nucleusnucleus ofofthethe femalefemale gametegamete..
-
DRM Biology Y10DRM Biology Y10 1313
FruitFruit andand seedseed formationformation
Once Once fertilisedfertilised,,�� TheThe OVARY OVARY
developsdevelops intointo thetheFRUIT.FRUIT.
�� TheThe OVULES OVULES becomebecome thethe SEEDSEED..
�� TheThe petalspetals, , stamenstamenandand stigmastigma shrivelshrivelandand fallfall..
-
DRM Biology Y10DRM Biology Y10 1414
FruitFruit andand seedseed dispersaldispersal
�� SeedsSeeds needneed toto be be disperseddispersed awayaway fromfromthethe parentparent plantplant. .
�� ThisThis can be can be achievedachievedby by windwind, , waterwater, , animalsanimals, , oror selfself--explosionexplosion..
�� EachEach seedseed has has specialspecial structuresstructuresadaptedadapted toto thethe wayway ititisis disperseddispersed..
-
DRM Biology Y10DRM Biology Y10 1515
SeedSeed structurestructure
� Seeds are protected by the testa.
� All seedshave a foodreserve (cotyledon).
� The embryo isformed by theplumule andthe radicle.
Plumule (futureshoot)
Radicle (futureroot)
cotyledon
Testa (seedcover)
cotyledon
EMBRYO
Radicle
PlumuleTesta
-
DRM Biology Y10DRM Biology Y10 1616
SeedSeed germinationgermination
All seeds must have waterwaterwaterwater, suitablesuitablesuitablesuitable
temperaturetemperaturetemperaturetemperature and oxygenoxygenoxygenoxygen to
germinate.
Some seeds may also need light to activate the
germination process.
Germination in a monocot plant (wheat)
Germination in a dicot plant (bean)