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xylem
xylèm m

Kesem. Wooden texture. Tissue within plants transports water and mineral salts absorbed by the roots from the soil to parts of the plant.

Kesem vessels are dead
Live kesm cells
Dispersed transverse walls
Two woods.

The cyst consists of vessels formed by columns of cells whose horizontal transverse walls have dispersed and their contents have died, forming long, continuous tubes. The vessels formed in this way are strengthened by a compound called lignin and eventually form the wood of the plant. In association with the xylem vessels, to provide additional strength, there are specialized cells called xylem fibres, some of which are useful, such as flax.
Therefore, cassim is of commercial importance as a source of wood and fibre. See leaf, root, secondary growth, and stem.