Mature xylem consists of elongated dead cells, arranged end to end to form continuous vessels tubes. Mature xylem vessels:. Phloem consists of living cells arranged end to end. Unlike xylem, phloem vessels contain cytoplasm, and this goes through holes from one cell to the next.
Phloem transports sucrose and amino acids up and down the plant. This is called translocation. The phloem is towards the centre, outside the xylem. In the stem, the transport tissues of the xylem and phloem are grouped into vascular bundles. Plant transport tissues - xylem and phloem Plants have two transport systems - xylem and phloem. Xylem The xylem transports water and minerals from the roots up the plant stem and into the leaves.
Vessels: Lose their end walls so the xylem forms a continuous, hollow tube. This allows water to flow easily.
Become strengthened by a chemical called lignin. The cells are no longer alive. Lignin gives strength and support to the vessel. Phloem Phloem moves sugar that the plant has produced by photosynthesis to where it is needed for processes such as: growing parts of the plant for immediate use storage organs such as bulbs and tubers developing seeds respiration Transport in the phloem is therefore both up and down the stem.
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Sign In or Create an Account. Sign In. Advanced Search. Search Menu. Article Navigation. Close mobile search navigation Article Navigation. Volume Article Contents Abstract. Linking xylem structural components and their functions.
Functionality of the xylem network: bottleneck for efficiency or smart design for safety? What is the appropriate approach to investigate the regulation of sap flow dynamics?
Toward real-time imaging of flow dynamics in the xylem network. Future directions. Investigating water transport through the xylem network in vascular plants.
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