Editing Plant cell (section)

===Sclerenchyma===
[[Ground tissue#Sclerenchyma|Sclerenchyma]] is a tissue composed of two types of cells, [[sclereid]]s and [[fibres]] that have thickened, [[lignin|lignified]] secondary walls<ref name=Cutter>{{cite book|first=EG |last=Cutter |date=1977 |title=Plant Anatomy Part 1. Cells and Tissues |publisher=Edward Arnold |location=London |isbn=0713126388 }}</ref>{{rp|78}} laid down inside of the [[primary cell wall]]. The secondary walls harden the cells and make them impermeable to water. Consequently, sclereids and fibres are typically dead at functional maturity, and the cytoplasm is missing, leaving an empty central cavity. [[Sclereid]]s or stone cells, (from the Greek skleros, ''hard'') are hard, tough cells that give leaves or fruits a gritty texture. They may discourage herbivory by damaging digestive passages in small insect larval stages. Sclereids form the hard pit wall of peaches and many other fruits, providing physical protection to the developing kernel. [[Fibre]]s are elongated cells with lignified secondary walls that provide load-bearing support and tensile strength to the leaves and stems of herbaceous plants. Sclerenchyma fibres are not involved in conduction, either of water and nutrients (as in the [[xylem]]) or of carbon compounds (as in the [[phloem]]), but it is likely that they evolved as modifications of xylem and phloem initials in early land plants.

[[Image:Arabidopsis-epiderm-conidiospore-hyaloperonospora-parasitica.jpg|thumb|right|cells of ''[[Arabidopsis thaliana]]'' [[Epidermis (botany)|epidermis]]]]