Presentation on theme: "Plant Structure and Growth & Plant Reproduction Emma Whisted."— Presentation transcript:
Plant Structure and Growth & Plant Reproduction Emma Whisted
Plant Structure and Growth Dicotyledonous Stem and Leaf Structure Epidermis: surface of the stem made of a number of layers often with a waxy cuticle to reduce water loss. Cortex Tissue: Forming a cylinder of tissue around the outer edge of the stem. Often contains cells with secondary thickening in the cell walls which provides additional support. Vascular bundle: contains xylem, phloem and cambium tissue. Xylem: a longitudinal set of tubes that conduct water from the roots upward through the stem to the leaves. Phloem: (sieve elements) transports sap through the plant tissue in a number of possible directions. Vascular cambium: a type of lateral meristem that forms a vertical cylinder in the stem. The cambium produces the secondary xylem and phloem through cell division in the vertical plane. Pith: In the center of the stem; composed of thin walled cells called parenchyma. In some plants this section can degenerate to leave a hollow stem. Stem
Cuticle: a waxy layer which reduces water loss through the upper epidermis. Upper epidermis: a flattened layer of cell that forms the surface of the leaf and makes the cuticle. Palisade Layer: the main photosynthetic region of the leaf. Vascular bundle: contains the transport system and vascular meristem tissue (x-xylem, p- phloem). Spongy mesophyll: contains spaces that allows the movement of gases and water through the leaf tissue.. Lower epidermis: bottom surface layer of tissues which contains the guard cells that form each stoma. Leaf Plant Structure and Growth Dicotyledonous Stem and Leaf Structure
Plant Structure and Growth Dicotyledonous vs. Monocotylonous plants
Plant Structure and Growth Distribution of Tissues in the Leaf (a)Phloem: transports the products of photosynthesis (sugars, amino acids). (b)Xylem: transports water and minerals into the leaf tissue from the stem and roots. (c)Epidermis: produces a waxy cuticle for the conservation of water. (d)Palisade: layer which is the main photosynthetic region. (e)Spongy layer: creates the spaces and surfaces for the movement of water and gases. (f)Lower epidermis: contains the stomata pores which allow gas exchange with the leaf. (g)xylem and phloem: combine in the vascular tissue to provide support to the leaf.
Plant Structure and Growth Apical and Lateral Meristems Apical: Primary growth; found at the tip of the root and the shoot, adding growth to the plant in these regions. Lateral: Also known as Cambium. Is the source of cells for secondary growth. Two types- cork cambium and vascular cambium.