Question

Which is not the function of the cell wall?
I. Provides shape to the cell.
II. Protects the cell from mechanical damage and infection.
III. Helps in cell to cell adhesion/attachment.
IV. Provides a barrier to undesirable macromolecules.
 V. Imbibes water.
(А) Only v
(B) Only IV
(С) Only II, IV and v
(D) None

Answer 1

Hint: Cell wall is located outside the cell membrane. It is defined as a structural layer which can be tough, flexible, and maybe rigid. It is well known for its structural support, protection and acts as a filtering mechanism. Its composition differs from species to species and may depend on cell type and developmental stage.

Complete Answer:
Let us see the functions performed by cell wall
- Provides shape to the cell: The cell wall serves as a hard layer of the cell and has tensile strength so it helps to provide shape to the cell.
- Protects the cell from mechanical damage and infection: The cell wall is located in plants outside the cell membrane. They show high tensile strength to withstand internal osmotic pressure so the cell wall prevents the cell from mechanical damage and infection.
- Helps in cell to cell adhesion/attachment: Glycocalyx is a slime layer and is capsule-like which is sticky in nature. It is composed of cell walls and it helps in attachment of cell to cell.
- Provides a barrier to undesirable macromolecules: The cell wall is semi permeable in nature so allows only some of the substances to pass through it and provides a barrier to undesirable molecules.
- Imbibes water: The cell wall acts as pressure vessels so they help in the imbibition of the water.

So, our required option is (D) that is None.

Note: Cell wall is the varying feature of plant cells. It gives rigidity and shape to the cell. It is located in the plant cells, bacteria, algae, fungi, and some archaea. Cell wall is defined as a highly complex structure which is located outside the plasma membrane. It is absent in animal cells.