药用植物学教案-叶的形态与结构.ppt

《药用植物学教案-叶的形态与结构.ppt》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、Chapter6TheLeafFunctionsFormandModificationsStructuresFunctionsPhotosynthesisRespirationTranspirationStorageFormThreeparts:LeafbladePetioleStipuleComplete,IncompleteLeafbladePetioleStipuleLeafTypesSimpleleafthebladeisallinonepiece,thoughitmaybelobed,toothed,etc.Compoundleaftheblade

2、isdividedallthewaytothemidrib(rachis)intotwoormorepieces(leaflets).Pinnate,Palmate,UnifoliateSimpleLeafCompoundLeafTheDifferencebetweenaStemwithSimpleLeavesandaCompoundLeaf1.Thetipoftherachisneverhasaterminalbud.2.Leafletsneverbearbudsintheiraxils.3.Leafletsalllieinthesameplane.4.T

3、herachisfallsoffwithleaflets.TheLeafMorphologyLeafshapesLeafmarginsLeafapicesLeafbasesLeaflobesLeafvenationLeaftextureLeafshapesLeafshapesLeafmarginsLeafapicesLeafbasesLeaflobesTheDifferencebetweenLeafletsandLobesPetiolules:existornotRachis:existornotArrangement:symmetricornotShape

4、sandSize:similarornotLeafvenationThePhyllotaxisGeneralrule:mosaicarrangement互生Spiral(Alternative)对生Opposite轮生Whorled簇生FascicledTheModifiedLeaves苞片Bracts鳞片Scales叶刺Spines(Thorns,Prickles)叶卷须Tendrils叶状柄Phyllodes捕虫叶Insecttraps异型叶性Heterophylly苞片Bracts苞片Bracts鳞片Scales鳞片Scales叶刺Spines叶卷须T

5、endrils叶状柄Phyllodes捕虫叶Insecttraps捕虫叶Insecttraps叶的内部结构表皮Epidermis叶肉组织Mesophyll维管组织Vasculartissues两种类型:两面叶Bifacialleaves:水平伸展等面叶Isolateralleaves:垂直伸展表皮Epidermis组成：扁平、板块状的表皮细胞；保卫细胞；表皮毛气孔的分布：两面叶：单侧性分布等面叶：对称性分布薰衣草叶LavenderLeafLavender-leaf花生叶PeaLeafStoma,Viceasp.(SEMx3,520).Cross-Sectio

6、nThroughaStomataSubsidiarycellGuardcellSubstamatalchamber叶肉组织Mesophyll两面叶：栅栏组织Palisademesophyll海绵组织Spongymesophyll等面叶：同型叶肉组织维管组织VascularTissues中脉与侧脉：维管束鞘初生韧皮部（下）初生木质部（上）小叶脉：逐渐简化