Usually the lower surface of a _____leaf has a greater number of stomata .

Explanation

**Step-by-Step Text Solution:**

1. **Understanding Leaf Types**: There are two main types of leaves: dicot leaves and monocot leaves. Dicot leaves are often referred to as dorsi-ventral leaves, meaning they have distinct upper (dorsal) and lower (ventral) surfaces.

2. **Structure of Dicot Leaves**: In dicot leaves, the upper surface is typically darker green due to the presence of palisade mesophyll cells, which are tightly packed and efficient for photosynthesis. The lower surface, on the other hand, contains spongy parenchyma and is usually lighter in color.

3. **Stomata Distribution**: Stomata are small openings on the leaf surface that allow for gas exchange and transpiration. In dicot leaves, the lower surface has a greater number of stomata compared to the upper surface. This adaptation helps reduce water loss through transpiration.

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