Question

Which of the following is/are made up of cellulose?
A. Cell membrane
B. Plasma membrane
C. Cell wall
D. All of the above

Answer 1

Hint: In plant cells, the cell components are covered by a layer of the cell wall, and in the case of animals no cell wall is present, but the layer is called the plasma membrane. The plasma membrane is generally proteinaceous. This is one of the major differences between plant and animal cells.

Complete answer:
Cell wall as the name implies is the protective covering or wall around the cells. Its components include lignin, cellulose, pectin, hemicellulose & many other proteins.
In the plant’s cell wall cellulose is the main component as it provides stiffness and support to the cell wall, humans cannot digest cellulose but the human body needs it as an important fiber but in bacteria cell walls there is no cellulose, and some bacteria can produce cellulose.
Functions of different cell wall components are:
1) Cellulose is the polymer of β-(1,4)-D-Glucose that provides the plants’ strength and maintains the cell shape, preventing cell desiccation.
2) Hemicellulose is a polysaccharide that helps in strengthening the cell wall through interaction with cellulose and lignin
3) Lignin is a complex polymer providing rigidity to the cell and tolerating many stresses in the wall.
4) Pectin cements the cellulose & hemicellulose network, which helps in plant defense and cell adhesion.
5) Plant cell proteins store Nitrogen, Carbon & Sulphur requirements in cell walls and plants.

The primary functions of the cell wall include:
a) Mechanical and structural support
b) Tolerating turgor pressure
c) Diffusion Regulation
d) Protection & storage
e) Communication
f) Growth regulation

So, the correct answer is option C) Cell Wall
 

Note: -
Cellulose is the most abundant macromolecule on earth. Humans cannot digest cellulose. Cellulose is used to make clothes and paper. It provides stiffness and support to the cell wall.