Basal cell of Ulothrix is

Options

A. Antheridium
B. Meristematic
C. Holdfast
D. Zoogonidium.

Answer

To solve the question "Basal cell of Ulothrix is," we need to analyze the options provided and understand the characteristics of the basal cell in Ulothrix.

### Step-by-Step Solution:

1. **Understanding Ulothrix**:
- Ulothrix is a genus of green algae commonly found in freshwater environments. It has a filamentous structure.

2. **Identifying the Basal Cell**:
- The basal cell in Ulothrix is a specialized cell that serves a specific function. It is located at the base of the filament.

3. **Function of the Basal Cell**:
- The primary role of the basal cell is to anchor the Ulothrix to a substrate, such as rocks. This anchoring is essential for stability and nutrient absorption.

4. **Modification of the Basal Cell**:
- The basal cell is modified into a structure known as the holdfast. The holdfast is responsible for the adherence of Ulothrix to surfaces.

5. **Analyzing the Options**:
- **Option 1: Antherium** - This refers to a male reproductive structure in plants, not related to the basal cell.
- **Option 2: Meristematic** - This refers to cells capable of division and growth, not specifically related to the basal cell of Ulothrix.
- **Option 3: Holdfast** - This is the correct option, as it is a modification of the basal cell that helps in anchoring.
- **Option 4: Zooholidium** - This term does not relate to Ulothrix or its basal cell.

6. **Conclusion**:
- Based on the analysis, the correct answer is **Option 3: Holdfast**.

### Final Answer:
The basal cell of Ulothrix is a **holdfast**.

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