Centromere is a part of:

Options

A. Chromosome
B. Endoplasmic reticulum
C. Ribosomes
D. Mitochondria

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Centromere**: The centromere is a specific region on a chromosome where two sister chromatids are joined together. It plays a crucial role during cell division, particularly in the separation of chromosomes.

2. **Identifying the Structure**: When we visualize a chromosome, it often appears as an "X" shape, which is formed by the two sister chromatids. The point where these chromatids are connected is called the centromere.

3. **Composition of the Centromere**: The centromere is not just a simple structure; it is a complex protein structure composed of various proteins that help in the proper functioning of the chromosome during cell division.

4. **Categorization of Chromosomes**: Based on the position of the centromere, chromosomes can be categorized into three types:
- **Metacentric**: The centromere is located in the middle, making the arms of the chromosome equal in length.
- **Telocentric**: The centromere is located at one end of the chromosome.
- **Acrocentric**: The centromere is slightly off-center, resulting in one arm being significantly shorter than the other.

5. **Evaluating the Options**: The question asks about what the centromere is a part of. The options provided include:
- Chromosome
- Endoplasmic Reticulum
- Ribosome
- Mitochondria

Among these, the centromere is specifically a part of the chromosome, making it the correct answer.

6. **Conclusion**: Therefore, the correct answer to the question "Centromere is a part of:" is **Chromosome**.

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