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Sap

From Wikipedia, the free encyclopedia
Sap droplets of Dracaena trifasciata

Sap is a fluid transported in xylem cells (vessel elements or tracheids) or phloem sieve tube elements of a plant. These cells transport water and nutrients throughout the plant.

Sap is distinct from latex, resin, or cell sap; it is a separate substance, separately produced, and with different components and functions.

Insect honeydew is called sap, particularly when it falls from trees, but is only the remains of eaten sap and other plant parts.[1]

Types of sap

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Saps may be broadly divided into two types: xylem sap and phloem sap.

Xylem sap

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Xylem sap (pronounced /ˈzləm/) consists primarily of a watery solution of hormones, mineral elements and other nutrients. Transport of sap in xylem is characterized by movement from the roots toward the leaves.[2]

Over the past century, there has been some controversy regarding the mechanism of xylem sap transport; today, most plant scientists agree that the cohesion-tension theory best explains this process, but multiforce theories that hypothesize several alternative mechanisms have been suggested, including longitudinal

Human uses

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Maple syrup is made from reduced sugar maple xylem sap.[3] The sap often is harvested from the sugar maple, Acer saccharum.[4]

In some countries (e.g., Lithuania, Latvia, Estonia, Finland, Belarus, Russia) harvesting the early spring sap of birch trees (so called "birch juice") for human consumption is common practice; the sap can be used fresh or fermented and contains xylitol.[5]

Certain palm tree sap can be used to make palm syrup.[citation needed] In the Canary Islands they use the Canary Island date palm while in Chile they use the Chilean wine palm to make their syrup called miel de palma.[citation needed]

See also

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References

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  1. ^ "How to Remove Tree Sap From a Car". HowStuffWorks. 20 August 2019. Retrieved 23 December 2020.
  2. ^ Template:Cite book/last=Marschner
  3. ^ Saupe, Stephen. "Plant Physiology". College of Saint Benedict and Saint John's University. Retrieved 3 April 2018.
  4. ^ Morselli, Mariafranca; Whalen, M Lynn (1996). "Appendix 2: Maple Chemistry and Quality". In Koelling, Melvin R; Heiligmann, Randall B (eds.). North American Maple Syrup Producers Manual. Bulletin. Vol. 856. Ohio State University. Archived from the original on 29 April 2006. Retrieved 20 September 2010.
  5. ^ Suzanne Wetzel; Luc Clement Duchesne; Michael F. Laporte (2006). Bioproducts from Canada's Forests: New Partnerships in the Bioeconomy. Springer. pp. 113–. ISBN 978-1-4020-4992-7. Archived from the original on 23 November 2017. Retrieved 6 April 2013.
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  • Media related to Plant sap at Wikimedia Commons