Which one of the following is resistant to enzyme action

Options

A. Pollen exine
B. Leaf cuticle
C. Cork
D. Wood fibre

Answer

To determine which of the following options is resistant to enzyme action, we will analyze each option provided: pollen enzyme, leaf cuticle, cork, and wood fiber.

### Step-by-Step Solution:

1. **Understanding the Options**:
- **Pollen Enzyme**: This is an enzyme produced by pollen grains. Enzymes are generally not resistant to other enzymes as they are biological catalysts that can be broken down by other enzymes.
- **Leaf Cuticle**: The cuticle is a waxy layer covering the leaves, which helps in reducing water loss. While it provides some resistance, it is not completely resistant to enzymes.
- **Cork**: Cork is a protective tissue that is also resistant to many environmental factors, but it can still be affected by certain enzymes.
- **Wood Fiber**: Wood fibers provide structural support and are somewhat resistant to degradation, but they can still be broken down by specific enzymes.

2. **Analyzing Pollen Grains**:
- Pollen grains are male gametophytes that develop in the anther of flowering plants.
- The outer layer of pollen grains is made of a substance called **sporopollenin**.

3. **Properties of Sporopollenin**:
- Sporopollenin is known to be one of the most resistant organic materials.
- It can withstand extreme conditions, including high temperatures and strong acids and alkalis.
- Importantly, no enzyme that can degrade sporopollenin has been identified, making it highly resistant to enzymatic action.

4. **Conclusion**:
- Given the properties of sporopollenin in pollen grains, the correct answer to the question "Which one of the following is resistant to enzyme action?" is **pollen grains**.

### Final Answer:
The correct option is **pollen grains** (Option 1).

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