Question

Question 30
Cork cells are made impervious to water and gases by the presence of

(a) cellulose
(b) lipids
(c) suberin
(d) lignin

Answer 1

(c) suberin

As plants grow older, the outer protective tissue undergoes certain changes. A strip of secondary meristem replaces the epidermis of the stem. Cells on the outside are cut off from this layer. This forms the several-layer thick cork or the bark of the tree.

Cells of cork are dead and compactly arranged without intercellular spaces. They also have a chemical called suberin on their walls that make them impervious to gases and water.