A type of plant cell in which the wall has been thickened to perform a structural role. Typically, fibres are elongated sclerenchyma cells with tapered ends and have fewer cavities in the thickenings than do other types of thickened cells, though neither feature is diagnostic. Such cells can be found in the cortex, phloem, and xylem. Commercially, the term refers to a strand of fibre cells, or to the epidermal cells (epidermis) of cotton or kapok seed pods. Flax and hemp fibres come from the phloem. Sisal is extracted from highly lignified leaf fibres of Agave. The name ‘fibre’ is also given to a fine or narrow root.
Subjects: Plant Sciences and Forestry.