Which of these is not found in the nucleus?

Options

A. Nucleoplasm instead of cytoplasm
B. Functioning ribosomes
C. Chromatin that condenses to chromosomes
D. Nucleolus that produces rRNA

Explanation

To determine which of the options is not found in the nucleus, we will analyze each option provided:

1. **Nucleoplasm**:
- The nucleoplasm is the semi-fluid substance found within the nucleus, similar to cytoplasm in the cell. It serves as a medium for the organelles within the nucleus.
- **Conclusion**: Nucleoplasm is found in the nucleus.

2. **Functioning Ribosomes**:
- Ribosomes are the cellular structures responsible for protein synthesis. They are not found within the nucleus; instead, they are located in the cytoplasm or attached to the endoplasmic reticulum.
- **Conclusion**: Functioning ribosomes are not found in the nucleus.

3. **Chromatin**:
- Chromatin is the complex of DNA and proteins found within the nucleus. It condenses to form chromosomes during cell division.
- **Conclusion**: Chromatin is found in the nucleus.

4. **Nucleolus**:
- The nucleolus is a dense structure within the nucleus that is responsible for producing ribosomal RNA (rRNA) and assembling ribosomes.
- **Conclusion**: The nucleolus is found in the nucleus.

After analyzing all the options, we find that the only structure not found in the nucleus is **functioning ribosomes**.

**Final Answer**: Functioning ribosomes are not found in the nucleus.

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