• State the functions of xylem and phloem
• Identify the position of xylem and phloem as seen in sections of roots, stems and leaves, limited to non-woody dicotyledonous plants
• Identify root hair cells, as seen under the light microscope, and state their functions
• State the pathway taken by water through root, stem and leaf as root hair cells, root cortex cells, xylem and mesophyll cells
• Investigate, using a suitable stain, the pathway of water through the above-ground parts of a plant
• Explain that the large surface area of root hairs increases the rate of the absorption of water by osmosis and ions by active transport
• State that water is transported from the roots to leaves through the xylem vessels
• Define transpiration as loss of water vapour from plant leaves by evaporation of water at the surfaces of the mesophyll cells followed by diffusion of water vapour through the stomata
• Investigate and describe the effects of variation of temperature and humidity on transpiration rate
• Explain how water vapour loss is related to the large surface area of cell surfaces, interconnecting air spaces and stomata
• Explain the mechanism by which water moves upwards in the xylem in terms of a transpiration pull that draws up a column of water molecules, held together by cohesion
• Explain how and why wilting occurs
• Explain the effects of variation of temperature and humidity on transpiration rate
• Define translocation in terms of the movement of sucrose and amino acids in phloem:
– from regions of production (source)
– to regions of storage OR to regions where they are used in respiration or growth (sink)
• Explain that some parts of a plant may act as a source and a sink at different times during the life of a plant