The point at which the polytene chromosomes appear to be attached together is known as

Options

A. centriole
B. centromere
C. chromomere
D. chromocentre

Explanation

To answer the question about the point at which polytene chromosomes appear to be attached, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Polytene Chromosomes**:
- Polytene chromosomes are specialized, giant chromosomes found in certain tissues of insects, particularly in the salivary glands. They are formed through a process called endomitosis or endoduplication, where the chromosomes replicate without cell division.

2. **Identify the Structure**:
- In polytene chromosomes, multiple copies of the chromosome are aligned side by side, which allows for the visualization of distinct light and dark bands when stained with basic dyes.

3. **Locate the Attachment Point**:
- The point where the chromatids of these polytene chromosomes are attached is a specific structure. This is crucial for understanding how these chromosomes maintain their integrity and organization.

4. **Define the Correct Term**:
- The attachment point of the chromatids in polytene chromosomes is known as the **chromocenter**. This is the region where the chromatids are joined together.

5. **Evaluate Other Options**:
- It's important to differentiate the chromocenter from other terms:
- **Centromere**: This is the region where sister chromatids are joined in typical chromosomes, but in polytene chromosomes, the term chromocenter is more appropriate.
- **Centrioles**: These are cell organelles involved in cell division but are not related to the structure of polytene chromosomes.
- **Chromomere**: This refers to the localized thickening along the chromosome but does not describe the attachment point.

6. **Conclude the Answer**:
- Therefore, the correct answer to the question is that the point at which the polytene chromosomes appear to be attached is called the **chromocenter**.

### Final Answer:
The point at which the polytene chromosomes appear to be attached is known as the **chromocenter**.

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