Modified stem which grows vertically to soil surface, bear nodes, internodes, buds and scaly leaves is

Options

A. bulb
B. corm
C. tuber
D. rootstock rhizome

Answer

To solve the question regarding the modified stem that grows vertically to the soil surface and bears nodes, internodes, buds, and scaly leaves, we will analyze the given options step by step.

### Step-by-Step Solution:

1. **Understanding the Question**:
- We need to identify a modified stem that grows vertically, has nodes, internodes, buds, and scaly leaves.

2. **Analyzing the Options**:
- The options provided are: **bulb, corm, tuber, and rootstock rhizome**.

3. **Evaluating Each Option**:
- **Bulb**:
- A bulb is an underground storage structure with fleshy scales and a basal plate. It does not primarily grow vertically; instead, it has apical growth. Thus, it does not fit the criteria.

- **Corm**:
- A corm is a vertical, fleshy, underground stem that acts as a food storage structure. It has nodes, internodes, buds, and scaly leaves. This matches the description provided in the question.

- **Tuber**:
- Tubers are swollen underground stems that serve as storage organs. They typically grow below the soil and have "eyes" but do not have distinct nodes and internodes. Therefore, this option does not fit.

- **Rootstock Rhizome**:
- A rhizome is a horizontal stem that grows underground and has nodes, internodes, and scaly leaves. However, it primarily grows horizontally rather than vertically, which disqualifies it from being the correct answer.

4. **Conclusion**:
- After evaluating all options, the only modified stem that grows vertically to the soil surface and possesses nodes, internodes, buds, and scaly leaves is the **corm**.

### Final Answer:
The modified stem which grows vertically to the soil surface, bears nodes, internodes, buds, and scaly leaves is **corm**.

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