Transport in plants Sunday, 28 April 2024 Key words: xylem, phloem, stomata Starter: How could you make this rainbow coloured rose? The big picture: “How do plants transport substances?” Learning outcomes To explain how substances are transported around a plant. To analyse how the xylem and phloem vessels are adapted to their functions. To evaluate the adaptations of the leaf to prevent water loss. Why do plants need transport systems? • They are multicellular- this means they have a higher demand for resources • Surface area : volume ratio- As organisms get bigger SA:V ratio gets smaller. This means diffusion alone is insufficient to supply resources. • The rate at which materials are required- if resources are required quickly a transport system is needed for efficient delivery. What materials do plants exchange & transport? • Carbon dioxide • Oxygen • Water • Glucose • Mineral ions Task: Explain why each of the above is required for by plants. Time allowed: 5 mins Task • Create a fact sheet on plant transport. • You need to include the xylem, phloem and stomata. • Diagrams and text should be used. • Follow the success criteria to reach the highest level possible. Support: Separate science text books, hand outs, phones Plenary Exam questions on transport in plants Time allowed: 12 mins Peer-assessment • Quality of written communication: for ideas given in a sensible order and a comparison made for geranium and cactus for each feature 1 • any four features + explanations from: 4 Peer-assessment (a) (i) root hairs (ii) xylem (iii) stomata1 (iv) storage organs 1 phloem 1 (b) (i) 1 1 23.2 1 (ii) loss of water (from flask with plant) from leaves / plant/stomata 1 • via transpiration / via evaporation 1 Resources Grade Criteria D State the functions of the xylem, phloem and stomata. C Draw diagrams to show how xylem and phloem are arranged in the stem and roots. B Explain the adaptations of plants that live in dry conditions. A Compare the structure of xylem and phloem. A* Evaluate how the structure of the xylem and phloem vessels allow them to effectively carry out their function. Challenge (A-level) Explain the difference between companion cells and sieve tube elements in the phloem Grade achieved: INT Included? Grade Criteria D State the functions of the xylem, phloem and stomata. C Draw diagrams to show how xylem and phloem are arranged in the stem and roots. B Explain the adaptations of plants that live in dry conditions. A Compare the structure of xylem and phloem. A* Evaluate how the structure of the xylem and phloem vessels allow them to effectively carry out their function. Challenge (A-level) Explain the difference between companion cells and sieve tube elements in the phloem Grade achieved: INT Included?