NOR is

Options

A. Nucleotide organising replicase
B. Nucleotide occluding region
C. Number of replicons
D. Nucleolar organising region

Answer

To answer the question "NOR is", we will break down the information step by step.

### Step-by-Step Solution:

1. **Understanding the Acronym NOR**:
- The acronym NOR stands for "Nucleolar Organizing Region". This is a specific term used in genetics and cell biology.

2. **Identifying the Function of NOR**:
- The Nucleolar Organizing Region is a part of the chromosome that plays a crucial role in the formation of the nucleolus. The nucleolus is a structure within the nucleus of eukaryotic cells that is involved in ribosome production.

3. **Locating NOR**:
- NOR is located on chromosomes. It is a specific region where the nucleolus forms around during cell division and is essential for the synthesis of ribosomal RNA (rRNA).

4. **Eliminating Incorrect Options**:
- The question provides several options:
- Nucleotide Organizing Replicase (incorrect)
- Nucleotide Oculating Region (incorrect)
- Number of Replicons (incorrect)
- The only correct option is the Nucleolar Organizing Region.

5. **Conclusion**:
- Therefore, the correct answer to the question "NOR is" is "Nucleolar Organizing Region".

### Final Answer:
NOR is the Nucleolar Organizing Region.

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