Structure of the xylem and phloem

• What are the two main functions of the xylem

  Transport water and mineral ions and for support
• is xylem tissue non living or living

  Non living
• What direction is the flow minerals in the xylem

  from the roots to the shoot
• What are the xylem vessels

  Hollow long tubes made up of columns of cells fused together end to end
• What is purpose of thick walled parenchyma 


  Packs around the xylem vessel storing food and containing tannin deposits
• What are tannin deposits I’m the xylem 


  A bitter astringent tasting chemical that protects palsy tissue from attack by herbivores
• What are xylem fibres

  Long cells with lignified walls to form extra strength, it can form rinhale, spirals or relatively solid tubes with small unlignified areas called pits
• What are border pits in the xylem

  Where water leaves the xylem
• is phloem tissue living or non living

  Living
• What is the purpose of the phloem


  Transport food in the form of organic solutes supplying the plant with amino acids and sugars
• What are phloem sieve tube elements made up of


  many cells joined end to end to form long hollow structure
• Are phloem Walls lignified

  no
• What are sieve plates

  The cell walls that have become perforated to allow the phloem contents through
• What are the companion cells linked to the sieve tube elements by

  by many plasmodesmata
• What is plasmodesmata 


  Microscopic channels through cellulose cell wall linking cytoplasm of adjacent cells
• What happens to the organelle in the sieve tube element

  they are broken down leaving phloem sap
• What are the supporting tissue for the phloem

  Fibres and sclereids cells which have extremely thick walls