Question

Specialised cells are generally found in the plant leaves which contain outgrowths of epidermal cell wall, made of calcium carbonate or silicon dioxide in a cellulose matrix are called as:

• A. Raphides
• B. Cystolith
• C. Druses
• D. Lithocysts

Hint:

To avoid confusion, remember the relationship: The \textbf{Cystolith} (the stone or mineral deposit) is found inside the \textbf{Lithocyst} (the stone-cell). The question asks for the cell, not the deposit within it.

Answer 1

The Correct Option is D

Step 1: Concept Summary:
The problem requires identifying the plant leaf cells specialized to contain mineral deposits. These deposits are outgrowths of the epidermal cell wall, composed of calcium carbonate or silicon dioxide within a cellulose matrix, representing plant biomineralization.
Step 3: Detailed Analysis:
Analyzing each option:
(A) Raphides: Needle-shaped calcium oxalate crystals within idioblast vacuoles. [11, 12, 14] Not cell wall outgrowths.
(B) Cystolith: Calcium carbonate concretion on a cellulose stalk, an epidermal cell wall outgrowth. [1, 5, 7] While the description of the *structure* is accurate, the question asks for the name of the specialized *cell* containing it.
(C) Druses: Star-shaped calcium oxalate aggregates within idioblast vacuoles. [11, 15, 16] Not cell wall outgrowths.
(D) Lithocysts: Specialized, enlarged epidermal cells containing cystoliths. [2, 8, 17] This directly answers the question regarding the specialized cell. The cystolith is within the lithocyst. [1, 10]
Therefore, lithocysts are the specialized cells that contain these outgrowths.
Step 4: Conclusion:
Option (D) is correct because lithocysts are the specialized epidermal cells housing cystoliths (calcium carbonate cell wall outgrowths). [2, 3, 8]