isobilateral leaves have stomata on

Options

A. both upper and lower surfaces
B. upper surface only
C. lower surface only
D. none of the surfaces.

Answer

### Step-by-Step Solution:

1. **Understanding Isobilateral Leaves**:
- Isobilateral leaves are characterized by having both surfaces that look alike and have similar structures. This is typically seen in monocotyledonous plants.

2. **Stomata Distribution**:
- In isobilateral leaves, stomata are present on both the upper and lower surfaces of the leaf. This means that the leaf has an equal distribution of stomata.

3. **Comparison with Other Leaf Types**:
- In contrast, dicot leaves are usually dorsiventral, meaning they have a distinct upper (dorsal) and lower (ventral) surface. In these leaves, stomata are primarily found on the lower surface to reduce water loss.

4. **Mesophyll Structure**:
- The mesophyll in isobilateral leaves is uniform, as opposed to dicot leaves which have differentiated mesophyll types (palisade and spongy). This uniformity contributes to the equal appearance of the leaf on both sides.

5. **Conclusion**:
- Therefore, isobilateral leaves have stomata on both the upper and lower surfaces. This characteristic allows for efficient gas exchange and is a key feature of monocot leaves.

### Final Answer:
Isobilateral leaves have stomata on both the upper and lower surfaces.

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