Question

Choose the correct statement:
I. Primary cell wall is capable of growth in mature plant cell  
II. Middle lamella is first formed layer of cell wall and it is the outermost layer in mature plant cell  
III. Addition of lignin into cellulose interfibrillar spaces leads to the formation of secondary cell in mature plant cell

• A. I, II, III
• B. I, II
• C. II, III
• D. I, III

Hint:

In plant cell development, the primary cell wall forms first and allows for growth, while the secondary cell wall (after lignin deposition) strengthens mature cells, allowing them to become rigid and provide structural support.

Answer 1

The Correct Option is C

Analyzing Each Statement

• I. Primary cell wall is capable of growth in mature plant cell: This statement is incorrect. The primary cell wall is capable of growth in young, developing cells, not in mature plant cells. In mature plant cells, it is the secondary wall (if formed) that provides strength and rigidity.
• II. Middle lamella is the first formed layer of the cell wall and it is the outermost layer in mature plant cells: This statement is correct. The middle lamella is indeed the first layer formed during cell division, and it lies between adjacent plant cells, forming the outermost layer in mature cells.
• III. Addition of lignin in cellulose inter-fibrillar spaces leads to the formation of the secondary cell wall in mature plant cells: This statement is correct. The secondary cell wall is formed in mature plant cells by the addition of lignin to the cellulose fibrils, which strengthens the wall.

Thus, the correct answer is (3) II, III.