noun, plural: sclerenchymata, sclerenchymas
In plants, the sclerenchyma is one of the three fundamental types of tissues. The other two are the collenchyma and the parenchyma. The cells that make up the sclerenchyma are distinct from those of collenchyma and parenchyma in having thick and tough cell wall. The sclerenchyma cell deposits a thick secondary cell wall in between the primary cell wall and the plasma membrane. Lignin is usually secreted and acts as a binder for the cellulose fibers. As such, the cell wall is tough and able to provide the plant structural strength. The cells usually lose their protoplast and as such are dead at maturity.
In angiosperms, the sclerenchyma is found in ground tissues and vascular tissues. In vascular tissues, there are two types, i.e. xylem sclerenchyma (includes fiber tracheids and libriform fibers) and phloem sclerenchyma (includes phloem fibers and sclereids). Both xylem and phloem sclerenchyma provide structural support to the vascular tissues. Bast fibers (i.e. phloem fibers in the secondary phloem) are collected for their commercial value.
Word origin: from Greek sklērós (“hard”) +énkhuma( “infusion”)
- sclerenchymatous (adjective, of, or pertaining to a sclerenchyma)