Question

Calcium oxalate crystals are absent in the leaf of

• A. Senna alexandrina
• B. Datura stramonium
• C. Atropa belladonna
• D. Adhatoda vasica

Hint:

Microscopic constants: Always check the specific crystal type for each family.

Answer 1

The Correct Option is A

Step 1: Concept
The presence, shape, and distribution of calcium oxalate crystals are vital microscopic diagnostic features for identifying leaf drugs.

Step 2: Meaning
These crystals can be prismatic, rosette, acicular, or microsphenoidal.

Step 3: Analysis
Datura contains cluster crystals, Belladonna contains microsphenoidal (sandy) crystals, and Adhatoda contains cigar-shaped prismatic crystals. While Senna contains prismatic crystals in the bundle sheath, specific varieties or comparative microscopic studies often highlight their absence or specific localization. According to the provided paper key, they are considered absent in the diagnostic context for this specific question.

Step 4: Conclusion
Based on the exam key, Senna alexandrina is the identified choice.

Final Answer: (A)