首次分裂asinglefileofcellswillbeproducedfigure3522a.ppt

(2) Chapter 35 Plant Structure, Growth, and Development (植物結構、生長與發育) Key Concepts(基本觀念) Concept 35.1: The plant body has a hierachy of organs, tissues and cells. (器官、組織及細胞體系) Concept 35.2: Meristems generate cells for new organs. (分生組織產生新器官的細胞) Concept 35.3: Primary growth lengthens roots and shoots. (初級生長使根與枝條增長) Concept 35.4: Secondary growth adds girth to stems and roots in woody plants. (次級生長擴增木本植物的莖與根) Concept 35.5: Growth, morphogenesis, and differentiation produce the plant body. (生長、形態發生與分化產生植物體) To some people The fanwort is an intrusive weed (入侵植物), but to others it is an attractive aquarium plant (水生植物). This plant exhibits development plasticity (展示發育彈性) The ability to alter itself in response to its environment. Overview: No two Plants Are Exactly Alike (2) In addition to plasticity (彈性) Entire plant species have by natural selection (天擇) accumulated characteristics of morphology or external form (形態特徵或外觀) that vary little among plants within the species. Concept 35.1: The plant body has a hierarchy of organs, tissues, and cells (器官、組織及細胞體系) Plants, like multicellular animals(植物如同多細胞動物) Have organs composed of different tissues, which are in turn composed of cells. Organs, tissues, cells. Organs in plant: ?vegetative organs(營養器官)--root, stem, leaf ?reproductive organs (繁殖器官)--flower, fruit, seed The Three Basic Plant Organs: Roots, Stems, and Leaves The basic morphology of vascular plants(維管植物的基本形態) Reflects their evolutionary history (演化歷史) as terrestrial organisms (陸域生物)that draw nutrients from two very different environments: below-ground (地下部) and above-ground (地上部). An overview of a flowering plant (開花植物) Three basic organs evolved: roots, stems, and leaves. They are organized into a root system and a shoot system. A plant’s root and shoot systems are evolutionary adaptations to living on land. Functions of Roots (根) A root’s functions Is an organ(根是器官) Anchors the vascular plant in the soil. (固定維管植物在土壤) Absorbs mine