- A Heat exposure alone, while showing essentially little resistance to either chemical or biological degradation processes occurring nearby naturally as widely reported in standard practice
- B Chemical degradation and biological attack (most powerful natural polymer), protecting pollen during transport -- only fluorescence microscopy and acetolysis can reveal patterns
- C Physical mechanical damage alone, while nevertheless remaining quite fragile and vulnerable to any chemical attack that occurs nearby under most conditions encountered as frequently observed in practice
- D UV radiation exposure alone, offering essentially little protection against any form of ongoing microbial degradation activity nearby in many documented cases according to conventional understanding
Correct answer: B. Chemical degradation and biological attack (most powerful natural polymer), protecting pollen during transport -- only fluorescence microscopy and acetolysis can reveal patterns
Explanation: Sporopollenin: extraordinarily resistant biopolymer in exine (outer pollen wall). Resistant to acids, bases, oxidants, and most biological degradation. Preserved for millions of years in fossil record.
Concept context
Flower structure, pollination, double fertilization, and seed/fruit development — the highest-scoring Class 12 biology chapter in NEET.
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