Chapter 17, Problem 30A

Summary Introduction

Introduction:

Plants are the organisms that have cell walls and tissues. They use their cell wall to maintain their rigidness and shape. A cell wall is a rigid layer which surrounds the cell and is located outside the plasma membrane. It provides additional strength and protection to the plasma membrane. The cell wall controls the plant cell to replicate at a much slower rate than animal cells.

Answer to Problem 30A

Correct answer :

The correct answer is option (D) Cellulose.

Explanation of Solution

Explanation/justification for the correct answer :

Option (D)Cellulose. Cellulose is the most important component of the cell wall of green plants. It is an important structural component as it helps to maintain the plants to remain stiff and strong. So, the correct answer is option (D).

Explanation for incorrect answer :

Option (A)Peptidoglycan. It is the main and specific component of most bacterial cell wall and provides structural strength to the unicellular bacteria. It also acts in counter acting the osmotic pressure of the cytoplasm and is involved in reproduction of bacteria by binary fission. So, this is an incorrect answer.

Option (B)Chitin. It is the primary component found in cell wall of fungi, exoskeleton of

insects and some invertebrates and fishes. It is a polysaccharides and forms a semitransparent

bony substance. So, this is an incorrect answer.

Option (C) Hyphae. Hyphae are found in fungi and actinobacteria and is a long, branching filamentous structure. In fungi, it is the main mode of vegetative growth. They absorb nutrition from the surroundings and transport to the other parts of the fungus body. So, this is an incorrect answer.