an undifferentiated mesophyll is found in

Options

A. isobilateral leaves
B. dorsiventral mesophytic leaves
C. dorsiventral xerophytic leaves
D. vertical leaves.

Answer

To answer the question "An undifferentiated mesophyll is found in:", we can follow these steps:

### Step-by-Step Solution:

1. **Understand Mesophyll**:
- Mesophyll is the inner parenchymatous tissue of leaves, primarily responsible for photosynthesis. It contains chloroplasts, which are essential for this process.

2. **Analyze the Options**:
- We have four options to consider:
1. Isobilateral leaves
2. Dorsiventral mesophytic leaves
3. Dorsiventral xerophytic leaves
4. Vertical leaves

3. **Evaluate Isobilateral Leaves**:
- In isobilateral leaves, the mesophyll is undifferentiated. It consists of spongy parenchyma without distinct layers, making it the correct answer.

4. **Evaluate Dorsiventral Mesophytic Leaves**:
- These leaves have a differentiated mesophyll structure, consisting of an upper layer of palisade parenchyma and a lower layer of spongy parenchyma. Thus, this option does not have undifferentiated mesophyll.

5. **Evaluate Dorsiventral Xerophytic Leaves**:
- Similar to dorsiventral mesophytic leaves, these also have a differentiated structure with three layers: upper palisade parenchyma, middle spongy parenchyma, and lower palisade parenchyma. Hence, this option is also not correct.

6. **Evaluate Vertical Leaves**:
- Vertical leaves also exhibit a differentiated mesophyll structure with three layers: upper palisade, middle spongy, and lower palisade parenchyma. Therefore, this option is incorrect as well.

7. **Conclusion**:
- After evaluating all options, we conclude that the correct answer is **Isobilateral leaves**, where the mesophyll remains undifferentiated.

### Final Answer:
**An undifferentiated mesophyll is found in Isobilateral leaves.**

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