A chromosome with only one arm is

Options

A. Acrocentric
B. Telocentric
C. Metacentric
D. Sub-metacentric

Answer

To answer the question "A chromosome with only one arm is," we need to analyze the different types of chromosomes based on their centromere position. Here's a step-by-step solution:

### Step-by-Step Solution:

1. **Understanding Chromosome Structure**:
- Chromosomes consist of two arms (p and q) that are separated by a centromere. The position of the centromere determines the type of chromosome.

2. **Identifying Chromosome Types**:
- **Metacentric Chromosome**: The centromere is located in the middle, resulting in two equal-length arms.
- **Submetacentric Chromosome**: The centromere is slightly off-center, leading to one arm being shorter than the other.
- **Acrocentric Chromosome**: The centromere is located closer to one end, resulting in one very short arm and one long arm.
- **Telocentric Chromosome**: The centromere is located at one end of the chromosome, resulting in only one arm being present.

3. **Analyzing the Options**:
- **Metacentric**: Incorrect, as it has two equal arms.
- **Submetacentric**: Incorrect, as it has one short and one long arm.
- **Acrocentric**: Incorrect, as it has one long and one very short arm.
- **Telocentric**: Correct, as it has only one arm due to the centromere being at one end.

4. **Conclusion**:
- A chromosome with only one arm is classified as a **telocentric chromosome**.

### Final Answer:
A chromosome with only one arm is **telocentric**.

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