Describe the Structures and Functions of Xylem Tissue - QS Study
QS Study

Xylem tissue: Xylem tissue is made of some living and dead cells. It carries water absorbed by root from soil to different parts of the plant body. Moreover, it also provides mechanical support to plant. Xylem tissue is composed of four component parts:

(1) Tracheid

(2) Trachea or vessel

(3) Xylem parenchyma and

(4) Xylem sclerenchyrna.

Tracheid:

  • It comprises of dead cells.
  • Cells are long and tapering of two ends.
  • Cell wall is hard, rigid and lignified. Pits are present in the wall.
  • The cells are attached.

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Trachia or vessel:

  • It consists of dead cells.
  • The cells are tubular and hollow inside. The cells that are connected end to end forming hollow tubes are called vessels.
  • The cell walls are lignified and they base bordered pits.
  • The xylems having very narrow diameter are called prow-xylem while the xylems having large diameter are called meta-xylem.

 

Xylem parenchyma:

  • The parenchyma cells that are present in xylem tissue are called xylem parenchyma. They are the only living cells of xylem tissue
  • The cells are elongated and cell walls are thin

 

Xylem fibre:

  • The sclerenchyma cells that are present in xylem tissue are called xylem fibre. They are also dead cells
  • The cells are narrow, elongated and pointed at the end.
  • Cell walls are thick, lignified and have bordered pits.

 

Functions of xylem:

  • Trachea or vessel carries water and minerals, absorbed by roots to leaves and other green parts of plant bodies
  • Tracheid of xylem tissue gives rigidity to plants and carries water and minerals from root to stem and leaf
  • Xylem fibre gives rigidity to plant organs