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1、Unit3Protectingourselves文化背景CannabisCannabisisanannual,dioecious,floweringherb.Theleavesarepalmatelycompound,withserrateleaflets.Thefirstpairofleavesusuallyhaveasingleleaflet,thenumbergraduallyincreasinguptoamaximumofaboutthirteenleafletsperleaf(usuallyseven
2、ornine),dependingonvarietyandgrowingconditions.Atthetopofafloweringplant,thisnumberagaindiminishestoasingleleafletperleaf.Thelowerleafpairsusuallyoccurinanoppositeleafarrangementandtheupperleafpairsinanalternatearrangementonthemainstemofamatureplant.Cannabis
3、normallyhasimperfectflowers,withstaminate"male"andpistillate"female"flowersoccurringonseparateplants.Itisnotunusual,however,forindividualplantstobearbothmaleandfemaleflowers.Althoughmonoeciousplantsareoftenreferredtoas"hermaphrodites,"truehermaphrodites(whic
4、harelesscommon)bearstaminateandpistillatestructuresonindividualflowers,whereasmonoeciousplantsbearmaleandfemaleflowersatdifferentlocationsonthesameplant.Maleflowersarenormallyborneonloosepanicles,andfemaleflowersareborneonracemes.AllknownstrainsofCannabisare
5、wind-pollinatedandproduce"seeds"thataretechnicallycalledachenes.MoststrainsofCannabisareshortdayplants,withthepossibleexceptionofC.sativasubsp.sativavar.spontanea(=C.ruderalis),whichiscommonlydescribedas"auto-flowering"andmaybeday-neutral.Cannabisisnaturally
6、diploid,havingachromosomecomplementof2n=20,althoughpolyploidindividualshavebeenartificiallyproduced.TheplantisbelievedtohaveoriginatedinthemountainousregionsnorthwestoftheHimalayas.Itisalsoknownashemp,althoughthistermisoftenusedtoreferonlytovarietiesofCannab
7、iscultivatedfornon-druguse.Cannabisplantsproduceagroupofchemicalscalledcannabinoids,whichproducementalandphysicaleffectswhenconsumed.Cannabinoids,terpenoids,andothercompoundsaresecretedbyglandulartrichomesthatoccurmostabundantlyonthefloralcalyxesandbractsoff
8、emaleplants.Asadrugitusuallycomesintheformofdriedflowerbuds(marijuana),resin(hashish),orvariousextractscollectivelyknownashashishoil.Intheearly20thcentury,itbecameillegalinmostoftheworldtocultiv