What is true of Parameciem

Options

A. Macronucleus takes part in reproduction
B. Macronucleus controls cellular metabolism
C. Micronucleus controls cellular metabolism
D. Micronucleus is not involved in reproduction.

Answer

To determine what is true of Paramecium, let's analyze the provided options step by step:

### Step 1: Understand the Structure of Paramecium
Paramecium is a unicellular organism that has two types of nuclei: the macronucleus and the micronucleus.

### Step 2: Functions of the Macronucleus
The macronucleus is responsible for performing common cellular functions, which includes controlling cellular metabolism. This means it plays a crucial role in the everyday metabolic activities of the Paramecium.

### Step 3: Functions of the Micronucleus
The micronucleus, on the other hand, serves as a storage site for germline genetic material. It is primarily involved in sexual reproduction, not in controlling cellular metabolism.

### Step 4: Evaluate Each Option
1. **Macronucleus takes part in reproduction**: This is incorrect. The macronucleus does not participate in reproduction; that role belongs to the micronucleus.

2. **Macronucleus controls cellular metabolism**: This is correct. The macronucleus is indeed responsible for cellular metabolism in Paramecium.

3. **Micronucleus controls cellular metabolism**: This is incorrect. The micronucleus does not control metabolism; it is involved in sexual reproduction.

4. **Micronucleus is not involved in reproduction**: This is incorrect. The micronucleus is involved in sexual reproduction.

### Conclusion
The only true statement about Paramecium from the options given is that the **macronucleus controls cellular metabolism**.

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