A: In sporoderm pecitocellulosic layer is surrounded by sproropollenin
R: Exine is differntiated into outer ektexine and inner endexine

Options

A. if both assetion A reason are ture and the reason is the correct explanation of the assertion then mark
B. if both assertion & reason are ture and the reason is not the correct explanation of the assertin then mark
C. if assertion is true statement but reason is false then mark
D. if both assertion and reason are flase statements then mark

Answer

To address the question regarding the assertion and reason about sporoderm and exine, we can break down the solution into several steps:

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that the sporoderm, which is the outer layer of the pollen grain, has a pectocellulosic layer that is surrounded by sporopollenin.
- This means that the outermost layer of the pollen grain is made of sporopollenin, which is a highly resistant substance.

2. **Understanding the Reason**:
- The reason states that the exine (the outer layer of the pollen grain) is differentiated into two parts: the outer layer called ectexine and the inner layer called endexine.
- This differentiation is based on their staining properties, which helps in identifying the two layers under a microscope.

3. **Evaluating the Assertion**:
- The assertion is correct because the sporoderm indeed consists of a pectocellulosic layer surrounded by sporopollenin. The sporopollenin provides protection to the pollen grain.

4. **Evaluating the Reason**:
- The reason is also correct as it accurately describes the structure of the exine, which is divided into ectexine and endexine.

5. **Determining the Relationship**:
- Although both the assertion and reason are true, the reason does not directly explain the assertion. The assertion discusses the composition of the sporoderm, while the reason elaborates on the structure of the exine.

6. **Conclusion**:
- Therefore, the correct interpretation is that both the assertion and reason are true, but the reason is not the correct explanation of the assertion.

### Final Answer:
The correct option is: Both assertion and reason are true, but reason is not the correct explanation of assertion.

---