Sclerenchyma Cell Walls are Hardened by What Substance

Question

Sclerenchyma cell walls are hardened by what substance?
A)pith
B)lignin
C)cellulose
D)cuticle
E)xylem

Accepted Answer

Sclerenchyma cells have thick secondary cell walls impregnated with lignin,a substance that makes plant cell walls tough and hard.If we compare a cell wall to reinforced concrete,cellulose fibrils would play the role of steel rods,and lignin would be analogous to the cement.