Nuclear membrane is absent in

Options

A. Volvox
B. Nostoc
C. Penicillium
D. Agaricus

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks which organism lacks a nuclear membrane. The nuclear membrane is a characteristic feature of eukaryotic cells, while prokaryotic cells do not have a true nucleus or nuclear membrane.

2. **Identify the Organisms**: The options provided are:
- A) Volvox
- B) Nostoc
- C) Penicillium
- D) Agaricus

3. **Classify Each Organism**:
- **Volvox**: This is a type of green algae and is classified as a eukaryote. Therefore, it has a nuclear membrane.
- **Nostoc**: This is a genus of cyanobacteria (also known as blue-green algae) and is classified as a prokaryote. Prokaryotes do not have a nuclear membrane.
- **Penicillium**: This is a genus of fungi and is classified as a eukaryote, meaning it has a nuclear membrane.
- **Agaricus**: This is also a genus of fungi and is classified as a eukaryote, which means it has a nuclear membrane.

4. **Determine the Correct Answer**: Since Nostoc is the only organism listed that is a prokaryote and lacks a nuclear membrane, it is the correct answer.

5. **Final Answer**: The nuclear membrane is absent in **Nostoc**.

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