Mature sclerenchyma cells are dead and have secondary cell walls
thickened with cellulose and usually impregnated with lignin. In contrast to
collenchyma, which is pliable, sclerenchyma is elastic. The cell cavity or lumen
is very small or it may disappear completely. There are two types of
sclerenchyma cells, namely sclereids and fibres.
- Sclereids: The cells are irregular in shape. The cell walls are thick, hard and
lignified which makes the lumen very small. Simple pits (canals) are found in the
thickened cell walls and link adjacent cells. Sclereids are commonly found in fruit and
- Fibres: The cells are needle-shaped with pointed tips, thick walls and rather
small lumen. Secondary cell walls, impregnated with, are formed. Simple pits are also
present. Fibres are abundant in the vascular tissue of angiosperms, i.e. flowering plants.
- sclerenchyma is an important supporting tissue in plants,
- sclereids are responsible for the hardness of date seeds and the shell of
- fibres probably play a role in the transport of water in the plant,
- starch granules are stored in the young, living fibres.
A line drawing of a sclerenchyma cell.