In which chromosome the centromere is situated close to its end forming one extremely short and one very long arm?

Answer

To answer the question "In which chromosome is the centromere situated close to its end, forming one extremely short and one very long arm?", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Chromosome Structure**:
- Chromosomes are structures made of DNA and proteins (histones) that carry genetic information. They have a distinct shape with two arms on either side of a central point called the centromere.

2. **Identifying Chromosome Arms**:
- Each chromosome has two arms: the short arm (commonly referred to as the "p arm") and the long arm (commonly referred to as the "q arm"). The centromere divides the chromosome into these two arms.

3. **Recognizing Chromosome Types**:
- Chromosomes can be classified based on the position of the centromere. If the centromere is located close to one end of the chromosome, it results in one very short arm and one very long arm. This type of chromosome is known as "acrocentric."

4. **Defining Acrocentric Chromosomes**:
- Acrocentric chromosomes are characterized by having the centromere positioned near one end, leading to a very short p arm and a much longer q arm. This structure is typical of certain chromosomes in humans, such as chromosomes 13, 14, 15, 21, and 22.

5. **Conclusion**:
- Therefore, the answer to the question is that the centromere is situated close to its end in acrocentric chromosomes.

### Final Answer:
The centromere is situated close to its end in acrocentric chromosomes.

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