पत्तों का हरा रंग किस तत्व के कारण होता है?

Question

पत्तों का हरा रंग किस तत्व के कारण होता है?

1. A. जिंक
2. B. नाइट्रोजन
3. C. क्लोरोफिल (Correct answer)
4. D. इनमें से कोई नहीं

Correct Answer

Option C — क्लोरोफिल

Detailed Solution & Explanation

The correct answer is क्लोरोफिल (chlorophyll).

Key Points

• Leaves are green because of chlorophyll, the pigment in chloroplasts that absorbs blue and red light and reflects green.
• Chlorophyll captures light energy for photosynthesis, converting CO₂ and water into glucose and oxygen.

Additional Information

• The central metal atom in chlorophyll is magnesium (Mg) — a favourite one-line exam fact. (In haemoglobin it is iron.)
• Nitrogen is needed to synthesise chlorophyll, which is why nitrogen deficiency causes yellowing (chlorosis) — this makes option (B) a tempting but indirect answer.
• Autumn colours appear as chlorophyll breaks down, revealing carotenoids and anthocyanins.