Which one of the following term is not a part of the nucleus?

Options

A. ribosome
B. nucleolus
C. chromosome
D. gene

Explanation

To determine which term is not a part of the nucleus, we will analyze each option provided.

### Step-by-Step Solution:

1. **Identify the Options**: We need to look at the given options to see which one does not belong to the nucleus. The options are:
- Option 1: Ribosomes
- Option 2: Nucleolus
- Option 3: Chromosome
- Option 4: Gene

2. **Analyze Option 1: Ribosomes**:
- Ribosomes are cellular structures that are responsible for protein synthesis. They are made of RNA and proteins but are not located within the nucleus. Instead, they are found in the cytoplasm or attached to the endoplasmic reticulum.

3. **Analyze Option 2: Nucleolus**:
- The nucleolus is a small, dense structure found within the nucleus. It is involved in the production and processing of ribosomal RNA (rRNA), which is essential for ribosome formation. Therefore, the nucleolus is indeed a part of the nucleus.

4. **Analyze Option 3: Chromosome**:
- Chromosomes are thread-like structures composed of DNA and proteins. They are located within the nucleus and contain the genetic information of the organism. Thus, chromosomes are part of the nucleus.

5. **Analyze Option 4: Gene**:
- A gene is a segment of DNA that contains the instructions for making a specific protein. Genes are located on chromosomes, which are found in the nucleus. Therefore, genes are also part of the nucleus.

6. **Conclusion**:
- After analyzing all the options, we find that the only term that is not a part of the nucleus is **Ribosomes** (Option 1). The other options (Nucleolus, Chromosome, and Gene) are all components or associated with the nucleus.

### Final Answer:
**Ribosomes** are not a part of the nucleus.

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