what differentiates a dicot leaf from monocot leaf

Options

A. Stomata only one of upper side
B. Differentiation of palisade and spongy parenchyma
C. Parallel venation
D. Stomata on the upper and lower sides

Answer

To differentiate a dicot leaf from a monocot leaf, we can analyze their structural characteristics step by step:

### Step 1: Understand the Structure of Dicot Leaves
- Dicot leaves have a well-defined structure that includes an upper and lower epidermis.
- The mesophyll (the tissue between the upper and lower epidermis) is differentiated into two types: palisade parenchyma and spongy parenchyma.
- Palisade parenchyma is located just below the upper epidermis and contains a higher concentration of chloroplasts, while spongy parenchyma is found below the palisade layer and has fewer chloroplasts.

### Step 2: Understand the Structure of Monocot Leaves
- Monocot leaves also have an upper and lower epidermis, but they differ in their mesophyll structure.
- In monocots, the mesophyll is generally undifferentiated, meaning that the cells do not form distinct palisade and spongy layers.
- Additionally, monocot leaves exhibit parallel venation, where the veins run parallel to each other.

### Step 3: Identify Key Differences
- One of the main differences is the differentiation of mesophyll: dicots have distinct palisade and spongy parenchyma, while monocots have undifferentiated mesophyll.
- Another difference is in the venation pattern: dicots typically have reticulate (net-like) venation, while monocots have parallel venation.
- Stomata in dicot leaves are usually absent on the upper epidermis, whereas in monocots, stomata are present on both the upper and lower epidermis.

### Conclusion
Based on these structural differences, we can conclude that the key differentiating factor between dicot and monocot leaves is the differentiation of mesophyll into palisade and spongy parenchyma in dicots, while monocots have an undifferentiated mesophyll.

### Final Answer
The differentiation of palisade and spongy parenchyma is what differentiates a dicot leaf from a monocot leaf.

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