Question

The cork tissue is made up of flattened, thin-walled cells whose walls are permeated by a waxy substance known as
A. Collagen
B. Elastin
C. Suberin
D. Reticulin

Answer 1

The woody plants stem and roots outer layer becomes dead when it gets matured known as Phellem or Cork. These are dead layers so they protect the inner parts of the woody plants from dryness and heat.

Complete answer:
The woody plants stem and roots outer layer becomes dead when it gets matured known as Phellem or Cork. These are the layers of dead cells and protect the inner parts of the woody plants from dryness and heat. Those plants that go for secondary growth the epidermis of the outer layer get destroyed as they have to grow in girth. Most of the dicots plants exhibit secondary growth like perennial gymnosperm, trees and exceptionally found in monocot plants such as Yucca , Dracaena , and palm. The secondary growth is done by lateral meristem that is by the vascular cambium and the cork cambium. So, to increase in girth the cork cambium that is also known as the phellogen it develops as the outer epidermal layer gets destroyed. The outer layers of phellogen or cork cambium develop the cork or Phellem and the inner layers develop the secondary cortex or phelloderm. The Phellem, phellogen and phelloderm together are known as periderm. The cork contains the waxy substance that helps the outer layer that is a cork from dryness as well as it helps from pathogens and bacteria. Suberin is a polyester biopolymer and is lipophilic in nature.

Hence, option C. is the correct answer.

Note:
Cork has wide economic importance that it is used in bulletin boards; another use is in hot pads to protect tables from hot pans, in wine bottle stoppers, in flooring, gaskets for engines. As it has great strength to weight cost so it is used in the satellite launch vehicle, in rocket motor nozzles and wind tunnels.