I know that the answer to the question "What is the difference between wood cells and human cells?" is in "Wood is a heterogeneous, hygroscopic, cellular and anisotropic material. It consists of cells, and the cell walls are composed of micro-fibrils of cellulose (40% – 50%) and hemicellulose (15% – 25%) impregnated with lignin (15% – 30%).". Can you tell me what it is?
A:
cell walls