The msot resistant biological material is present in the

Options

A. Endothecium of anther
B. Stopmium of anther
C. Exine of pollen grian
D. Intine of pollen grain

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks about the most resistant biological material present in flowering plants.

2. **Identifying Key Terms:**
The key terms to focus on are "resistant biological material" and "pollen grain."

3. **Analyzing the Options:**
The options provided are:
- Endothelium of anther
- Stropium of anther
- Enzyme of pollen grain
- Exine of pollen grain
- Entine of pollen grain

4. **Examining Pollen Grains:**
Pollen grains are the male gametes in angiosperms. They have two layers: the outer layer (Exine) and the inner layer (Entine).

5. **Identifying the Most Resistant Material:**
The Exine, which is the outer layer of the pollen grain, is made up of a substance called Sporopollenin. Sporopollenin is known to be one of the most resistant organic materials.

6. **Properties of Sporopollenin:**
Sporopollenin can withstand extreme conditions, such as high temperatures and strong acidic or alkaline environments. It is also resistant to degradation by enzymes.

7. **Conclusion:**
Based on the analysis, the most resistant biological material is found in the Exine of pollen grains.

**Final Answer:**
The most resistant biological material is present in the Exine of pollen grains.

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