Sieve tube element - wikipedia Sieve tube element This article includes a list of references, related reading or external links, but its sources remain unclear because it lacks inline citations. Please help to improve this article by introducing more precise citations. ( May 2015 ) Companion cell ( left, light pink ), nucleus ( dark pink ), sieve tube ( right, solid green ), sieve tube plates ( dashed green ), dissolved nutrients ( yellow ) In plant anatomy, sieve tube elements, also called sieve tube members, are highly specialised type of elongated cell in the phloem tissue of flowering plants. The ends of these cells are connected with other sieve tube members, and together they constitute the sieve tube. The main function of the sieve tube is transport of carbohydrates, primarily sucrose, in the plant ( e.g., from the leaves to the fruits and roots ). Unlike the water - conducting xylem vessel elements that are dead when mature, sieve elements are living cells. They are unique in lacking a nucleus at maturity. At the interface between two sieve tube members in angiosperms are sieve plates, pores in the plant cell walls that facilitate transport of materials between them. Each sieve tube element is normally associated with one or more nucleated companion cells, to which they are connected by plasmodesmata ( channels between the cells ). Each companion cell is derived from the same mother cell as its associated sieve tube member. Sieve tube members have no cell nucleus and ribosomes,, thus they depend on companion cells to provide proteins, ATP, and signalling molecules. In leaves, companion cells help move the sugar that is produced by photosynthesis from the mesophyll tissue into the sieve tube elements. Sieve cells are long, slender, conducting cells of the phloem that do not form a constituent element of a sieve tube, but which are provided with relatively unspecialized sieve areas, especially in the tapering ends of the cells that overlap those of other sieve cells. Sieve cells are typically associated with gymnosperms, because angiosperms have the more derived sieve tube members and companion cells in their phloem. They have a narrower diameter and are more elongated compared to sieve tube members. Sieve cells are associated with albuminous cells ( also called Strasburger cells ), which lack starch, thus making it possible to differentiate them from phloem parenchyma. The forest botanist Theodor Hartig was the first to discover and name these cells as Siebfasern ( sieve fibres ) and Siebröhren ( sieve tubes ) in 1837. See also Phloem Vascular tissue External links Comprehensive explanation of sieve elements - University of Hamburg Department of Biology Introduction to secondary phloem tissue by Dr. David T. Webb - University of Hawaii References Katherine Esau ( 1969 ). The Phloem - in : Encyclopedia of Plant Anatomy. Gebrüder Borntraeger, Berlin, Stuttgart. Campbell, N.A. ( 1996 ) Biology ( 4th edition ). Benjamin Cummings NY. ISBN 0 - 8053 - 1957 - 3 Hartig, T. ( 1837 ) Vergleichende Untersuchungen über die Organisation des Stammes der einheimischen Waldbäume. Jahresber. Fortschr. Forstwiss. Forstl. Naturkd. 1 : 125 - 168 Biological tissues Animals Epithelial Connective Muscular Nervous Plants Dermal tissue : Epidermis Cuticle Pavement cell Guard cell Subsidiary cell Periderm Phellem Phelloderm Vascular tissue : Phloem Sieve tube Companion cell Phloem fiber Phloem parenchyma Xylem Tracheid Vessel element Xylem fiber Xylem parenchyma Ground tissue : Parenchyma Aerenchyma Chlorenchyma Mesophyll Pith Collenchyma Sclerenchyma Sclereid Fiber Meristematic tissue : Primary Protoderm Procambium Ground meristem Secondary Cork cambium Vascular cambium Mixed : Cortex Exodermis Endodermis Stele Histology Retrieved from `` https://en.wikipedia.org/w/index.php?title=Sieve_tube_element&oldid=823322263 '' Categories : Plant anatomy Plant physiology Tissues ( biology ) Hidden categories : Articles lacking in - text citations from May 2015 All articles lacking in - text citations Talk About Wikipedia Català Čeština Español Français Latviešu Polski Português Русский தமிழ் ไทย Tiếng Việt 4 more Edit links This page was last edited on 31 January 2018, at 15 : 34. Text is available under the Creative Commons Attribution - ShareAlike License ; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia ® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization. About Wikipedia

Question: name the cell which is attached to the lateral side of sieve tube
Answer: sieve tube elements