Parenchyma, collenchyma, and sclerenchyma differ significantly in their cell wall composition and thickness. Parenchyma cells have thin, primarily cellulose-based walls. Collenchyma cells possess thick, non-lignified walls with cellulose and pectin, especially at the corners. Sclerenchyma cells have thick, lignified walls providing rigidity and mechanical support, often with secondary wall thickening.
Parenchyma:
Cell Wall Thickness: Thin.
Cell Wall Composition: Primarily cellulose.
Function: Storage, photosynthesis, support in young plants.
Collenchyma:
Cell Wall Thickness: Thick, especially at the corners.
Cell Wall Composition: Cellulose and pectin.
Function: Mechanical support, especially in young, growing parts of plants.
Sclerenchyma:
Cell Wall Thickness: Thick and rigid.
Cell Wall Composition: Lignin, which is a waterproofing material.
Function: Mechanical support, particularly in mature, non-growing regions of plants.