taniyaMadiwal taniyaMadiwal 04.07.2019 Science Secondary School Functions of phloem cell… The cells of the metaphloem function until the secondary phloem is formed in plants with cambium. 1. Mainly contains living cells (fibers are the only dead cells in the phloem). The sugars are moved from the source, usually the leaves, to the phloem … See color plate 10. Sieve tube elements Companion cells How is phloem’s structure related to its function? Xylem and phloem give vascular plants their classification; they are the vascular tissues that transport substances throughout the plant. Moreover, it was reported that the gain-of-function mutant bes1-D sometimes exhibits reduced procambial cell layers between xylem and phloem cells due to the excess vascular differentiation from procambial cells (Kondo et al. non-photosynthetic root cells or developing flowers). Through the system of translocation, the phloem moves photoassimilates, mainly in the form of sucrose sugars and proteins, from the leaves where they are produced by photosynthesis to the rest of the plant. Veins consist of at least seven distinct cell types, with specific roles in transport, metabolism, and signaling. Pathogens such as viruses utilize the phloem for systemic infection. - Phloem cells have relatively few organelles but are kept alive by companion cells. Although its primary function is transport of sugars, phloem may also contain cells that have a mechanical support function. Both cell types have a secondary cell wall and are therefore dead at maturity. lobelia and taraxacum) (Fig. Its main function is to carry organic nutrients from the stems, to the growing tissues and storage tissues. Functions of Phloem Tissue Phloem tissue perform following functions in plants 1. Both are components of vascular tissues in plants that serve the purpose of transporting materials … All organisms, and in particular multicellular ones, need to maintain functional coherence. Plant cells are the building blocks of plants. -companion cells support sieve element cells as they perform certain metabolic functions for sieve elements -microscopic pores in cell walls are larger to allow for exchange of metabolites how does the structure of phloem sieve tubes relate to its function? In this network, the products of photosynthesis are distributed … When phloem cells mature, they are living tissues but do not contain a nucleus. Start studying Phloem structure and function. The total amount of phloem tissue is less. The function of the phloem tissue is to transport food nutrients such as sucrose and amino acids from the leaves and to all other cells of the plant, this is called translocation. Given the importance of the tissue, it is astounding that the functional basis is still not understood satisfactorily. The high content of photoassimilates in sieve tubes attracts an armada of insects, for instance aphids, white flies, or leaf hoppers, that impale their stylets directly into sieve tubes to feed on their contents. The basic elements of phloem are fibers, sieve tubes, sieve cells, parenchyma, and companion cells. PP effluxes sucrose into the apoplasm as a basis for phloem loading; yet PP has only been characterized microscopically. The cells in vascular tissue are typically long and slender. The phloem is also a pathway to signaling molecules and has a structural function in the plant body. Phloem cells do not provide mechanical support to plants. 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