Chapter 4, Problem 3CT

Summary Introduction

To explain: A secondary cell wall forms on the inner side of the primary cell wall in plants instead of on the outer surface of it.

Concept introduction:

The plants are enclosed by cell wall secreted by extracellular matrix. It is the thin layer formed on the outer surface of the plasma membrane and allows the cell to enlarge during the growth. It is known as the primary cell wall. In some plants, such as woody plants, a secondary cell wall forms on the inner side of the primary cell wall. It is composed of lignin that is found in the xylem walls and fiber cells of woody tissues.