Ferns contain underground stem called ………….. .

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the name of the underground stem found in ferns.

2. **Understanding Ferns**: Ferns are a type of vascular plant that reproduce via spores and have a distinct life cycle involving a sporophyte and gametophyte stage.

3. **Recognizing the Structure**: In ferns, there is a specific structure that serves as an underground stem. This structure is essential for the plant's growth and stability.

4. **Naming the Structure**: The underground stem in ferns is called a "rhizome."

5. **Function of the Rhizome**: The rhizome serves multiple functions:
- It provides anchorage to the plant, helping it stay rooted in the soil.
- It aids in the transportation of water and nutrients throughout the plant.

6. **Final Answer**: Therefore, the underground stem found in ferns is called a **rhizome**.

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