北京大学：《植物生物学 Plant Biology》精品课程教学资源（电子教案）第11讲 叶

叶的形态与功能 Morphology and Functions of leaf ●叶的功能 functions ●光合作用 blade or photosynthesis 蒸腾作用 transpiration margin 其它合成作用 ●叶的形态组成 midrib 叶片 blade or lateral lamina veins ●叶柄 petiole petiole ●托叶 stipule stipules stem

叶的形态与功能 Morphology and Functions of Leaf z 叶的功能 functions functions z 光合作用 photosynthesis photosynthesis z 蒸腾作用 transpiration transpiration z 其它合成作用 z 叶的形态组成 z 叶片 blade or blade or lamina z 叶柄 petiole petiole z 托叶 stipule stipule

完全叶和不完全叶 Complete or Incomplete leaf Close-up of Barley Stem Node Monocotyledon) Blade Stem Auricles Ligule Sheath

完全叶和不完全叶 Complete or Incomplete leaf

Simple leaves of thottea Aristolochiaceae 马兜铃科

Simple leaves of Thottea Aristolochiaceae 马兜铃科

舌 The pinnately Sessile leaves of a In corn the base of the compound leaf of Member of the mustard leaf forms a sheath the pea(Pisum famil around the stem sativum

The pinnately compound leaf of the pea (Pisum sativum). Sessile leaves of a Member of the mustard family. In corn, the base of the leaf forms a sheath around the stem. ￩叶舌 托叶

Perfoliate leaf 穿茎叶

Perfoliate leaf 穿茎叶

The leaf of alfalfa苜蓿( Medicago sp.)

The leaf of alfalfa 苜蓿（Medicago sp. ）

Peltate leaf盾状叶

Peltate leaf 盾状叶

单叶与复叶 Simple and compound leaf 单叶 simple leaf ●复叶 compound leaf ●羽状复叶 pinnately compound leaf ●掌状复叶 palmately compound leaf pal mately compound leaf leaflets RED BUCKEYEBLACK HONEY (Aesculus) LOCUST LOCUST (Robinia)

单叶与复叶 Simple and Compound leaf z 单叶 simple leaf simple leaf z 复叶 compound leaf compound leaf z 羽状复叶 pinnately pinnately compound leaf compound leaf z 掌状复叶 palmately palmately compound leaf compound leaf

How to distinguish simple and compound leaves? (1) Axillary bud(腋芽的有无) buds could be found in leaf axils of both simple and compound leaves but not in the axils of leaflets (2) Terminal bud(顶芽) (3 Leaf and leaflets differ in the ways arranging in stem and petiole(叶的排列方式) leaves extend from the stem in various directions whereas the leaflets of a given leaf all lie in the same plane

How to distinguish simple and compound leaves ？ (1) Axillary bud (腋芽的有无）—— buds could be found in leaf axils of both simple and compound leaves, but not in the axils of leaflets (2) Terminal bud （顶芽） (3) Leaf and leaflets differ in the ways arranging in stem and petiole （叶的排列方式）—— leaves extend from the stem in various directions, whereas the leaflets of a given leaf all lie in the same plane