Accessibility options


phloem

Phloem  
Part of the National cirriculum

vascular bundle - Click to enlarge
Click image to enlarge

Tissue found in vascular plants. Its main function is to transport sugars and other food materials such as amino acids (see protein) from the leaves, where they are produced, to all other parts of the plant. This could be from the leaves to the roots to provide the chemicals needed for growth. However, it could be from a leaf and up to a developing fruit that is rich in sugars. The sugars are made by photosynthesis, which occurs in green parts of plants, such as leaves (see leaf). The amino acids are made from sugars and minerals, such as nitrate absorbed from the soil. Phloem tissue is usually found close to the other transport tissue in plants, xylem, which transports water and minerals. In non-woody plants phloem and xylem are found in bundles, such as the veins of a leaf.

Phloem is composed of sieve elements and their associated companion cells, together with some sclerenchyma and parenchyma cell types. Sieve elements are long, thin-walled cells joined end to end, forming sieve tubes; large pores in the end walls allow the continuous passage of nutrients. Phloem is usually found in association with xylem, the water-conducting tissue, but unlike the latter it is a living tissue.

© RM 2009. Helicon Publishing is division of RM.


 
 

Encyclopaedia Search

Click a letter for the index
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Or search the encyclopaedia:
 
 
All results tagged with the symbol denotes content that is relevant to the national curriculum

Advertisement starts



Advertisement ends


Advertisement starts



Advertisement ends

Country Search

 
 

Dictionary search

 
 

Russian Federation Flag

Russian Federation Flag
White, blue, and red became known as the pan-Slavic colours, influencing many other Eastern European flags. White, blue, and red are also the colours of the arms of the Duchy of Moscow. Effective date: 11 December 1993.

Health Search

 
 
Search all Diseases Medicines

Advertisement starts



Advertisement ends

Skip to page content | Text onlyGraphical version of this page

Tiscali Quicklinks. Please visit our Accessibility Page for a list of the Access Keys you can use to find your way around the site, skip directly to the main navigation, to the page content, or to more links within reference.

web |  shopping |  this site |  video |  local services

Page Footer


Access keys


You will need to use different key combinations in order to use access keys depending on your internet browser, find out which on our accessibility page.
  • (0) Navigate to Accessibility page.
  • (1) Navigate to Home page.
  • (2) Navigate to My email.
  • (3) Navigate to My Account.
  • (4) Navigate to Site Map page.
  • (5) Navigate to Contact us page.
  • (6) Navigate to Members channel.
  • (7) Navigate to Services channel.
  • (8) Navigate to News & Info channel.
  • (9) Navigate to Entertainment channel.
  • ([) Skip down to the Primary navigation block.
  • (]) Skip down to the more links within this section block.
  • (=) Bypass all navigation and jump to the content.
  • (x) Text only version of this page.
Background images used:
furniture images used in the site icons used in the site images used in the header