In which of the following , phloem occurs in two patches ?

Options

A. Maize
B. Cucurbita
C. Sunflower
D. Dracaena

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks about the occurrence of phloem in two patches within a specific type of vascular bundle.

2. **Identify Vascular Bundle Types**: There are different types of vascular bundles in plants, including:
- Collateral
- Bicollateral
- Concentric
- Radial

3. **Define Bicollateral Vascular Bundles**: In bicollateral vascular bundles, phloem occurs in two patches, one on each side of the xylem. This is a unique arrangement compared to other types of vascular bundles.

4. **Know the Families**: Bicollateral vascular bundles are typically found in certain plant families, notably:
- Cucurbitaceae (e.g., cucumbers, pumpkins)
- Solanaceae (e.g., tomatoes, potatoes)

5. **Evaluate the Options**:
- **Option A: Maize** - Maize has collateral vascular bundles, not bicollateral. (Incorrect)
- **Option B: Cucurbita** - This belongs to the Cucurbitaceae family and has bicollateral vascular bundles. (Correct)
- **Option C: Sunflower** - Sunflower has collateral vascular bundles. (Incorrect)
- **Option D: Raccana** - This does not belong to the Cucurbitaceae or Solanaceae family. (Incorrect)

6. **Conclusion**: The correct answer is **Option B: Cucurbita**, as it is the only option where phloem occurs in two patches (bicollateral vascular bundles).

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