Pollen grains can be preserved as fossil because

Options

A. they vary from species to species
B. they have a wide variety of architecture.
C. their wall is made up of sporopollenin
D. they exhibit a fascinating array of patterns and design

Answer

**Step-by-Step Solution:**

1. **Understanding Pollen Grains**: Pollen grains are the male gametophytes of seed plants and play a crucial role in reproduction. They are produced by the anthers of flowers and are essential for fertilization.

2. **Composition of Pollen Grains**: The outer layer of pollen grains is made up of a substance called sporopollenin. This is a key component that contributes to the preservation of pollen grains.

3. **Properties of Sporopollenin**: Sporopollenin is known for its remarkable resistance to various environmental factors. It is highly resistant to degradation by acids, bases, and even microbial attack.

4. **Fossilization Process**: Fossilization typically requires that the organism or material be preserved in a way that prevents decay. The durability of sporopollenin allows pollen grains to withstand harsh conditions over long periods, making them more likely to be preserved as fossils.

5. **Conclusion**: Therefore, the reason pollen grains can be preserved as fossils is primarily due to the presence of sporopollenin in their walls, which provides resistance to acidic and alkaline environments.

6. **Correct Answer**: The correct option is that pollen grains can be preserved as fossils because their walls are made up of sporopollenin.

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