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Structure of the Flowering Plant. Organisation of a flowering plant. A flowering plant is divided into two portions: a shoot system and a root system. The shoot system. Buds growth tissues – can produce new stems, leaves and flowers Axial buds – grow on side of stem
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Organisation of a flowering plant A flowering plant is divided into two portions: a shoot system and a root system
The shoot system Buds growth tissues – can produce new stems, leaves and flowers Axial buds – grow on side of stem Apical bud – grows on top of stem The shoot system is made up of stems, leaves, flowers and buds Flowers Reproductive organs Leaves Where photosynthesis takes place Stem Give support for leaves and flowers transport food and water around the plant
The shoot system Petiole the stalk of a leaf Node The place on the stem that leaves grow from Internode the part of the stem between two nodes
The leaf structure A leaf with a petiole A sessile leaf – no petiole
Venation is the pattern of veins on a leaf Leaf venation Net venation
The root system The roots anchor the plant in the soil, absorb water and minerals from may store food Primary root The main root that came out of the seed Secondary root Roots that come out of the primary root. They have root hairs which help to absorb water and minerals from the soil
Root zonations Vascular tissue Zone of differentiation Elongated cells develop into different types of tissue – dermal tissue,ground tissue or vascular tissue Ground tissue Dermal tissue Zone of elongation the new cells made grow longer here Root hairs Zone of production Cells in the meristem of the root divide by mitosis to make new cells Meristem Zone of protection Root cap protects the root cells as they go into the soil Root cap
The meristem tissue The meristem tissue produces new cells, which then become specialised. • It is found in the shoot and root apices ( tips ) and is called apical meristem tissue.
The specialisation of cells • specialise - change their structure to carry out special jobs in the plant • They will become: Dermal tissue (forms the protective covering of plants) or Ground Tissue (fills the inside of the plant) or Vascular tissue (transports water and nutrients around the plant)
The root Dermal Tissue Ground Tissue
Prepare and examine the transverse section of a dicot stem under a microscope • Cut a section of internodal stem from the celery using a chopping board • Carefully cut thin cross sections at a 90o angle using a wet blade. Cut away from yourself! • Place cut sections of stem in a Petri dish of water. • Make up a microscope slide of the stem piece. • Examine under the microscope using X100 and x400 magnifications • Draw a sketch of the image seen
Step 1 Collect suitable plant, e.g.celery, geranium. Cut a short section of the stem between two nodes. Use a chopping board!
Step 2 Hold the stem securely and cut several thin sections at 90° to the stem using a wet blade. Cut away from fingers.
Step 3 Place the sections in water. Transfer to a slide using a paintbrush.
Step 4 Add a few drops of water and a coverslip at an angle. Observe under the microscope.
Experiment Questions TS Dicot Stem
The Leaf Ground Tissue Dermal Tissue Vascular Tissue Found in the centre of the leaf .
Tissue Location in the Leaf Dermal Tissue Ground Tissue Vascular Tissue Dermal Tissue
Vascular Tissue • Vascular Tissue transports materials around the plant • It is made up of xylem and phloem tissue
Xylem Xylem tissue is used to transport water around the plant and to support it There are two types of xylem cells tracheid cells and vessel cells Both cells have no cytoplasm and both have lignin in their cell walls, which strengthens them
Movement between xylem cells Xylem Tracheids Xylem Vessels Found in conifers Found in deciduous trees
Xylem tissue Tracheid cells have narrow ends with holes in their walls called pits. Vessel cells are larger cells with no end wall to allow water to flow uninterrupted from one vessel cell to the next
Phloem tissue Phloem tissue is used to transport nutrients and sugars around the plant There are two types of phloem cells: Sieve tube element cells and companion cells Companion cells
Sieve Tube element cells • long and thin cells with no nucleus. • They have holes in their end walls which are called “sieve plates” • Companion cells • have a nucleus which controls both cells • Are in control of the movement of materials in the sieve plates.
Flowering Plants Two classes: monocotyledons “monocots” and dicotyledons “dicots”
Monocots Have a single cotyledon ( a leaf inside the seed where food is stored) Leaves have parallel venation They have scattered vascular bundles They have flowers arranged in groups of three They are usually soft plants, with no woody parts “Herbaceous”
Dicots Have two cotyledons Leaves have net venation They have vascular bundles arranged in a ring They have flowers arranged in groups of four or five They can be Herbaceous or woody
