Arrangement of microtubules in basal bodies is

Options

A. 9 pairs in circle
B. 9 triplets in circle
C. 9 pairs in circle + 2 axial
D. 2 in circle and 9 in periphery

Answer

### Step-by-Step Solution:

1. **Understanding Basal Bodies**: Basal bodies are structures that anchor cilia and flagella in eukaryotic cells. They are similar in structure to centrioles.

2. **Microtubule Arrangement**: The arrangement of microtubules in basal bodies is crucial for their function. They are made up of microtubules that are organized in a specific pattern.

3. **Identifying the Correct Pattern**: The arrangement of microtubules in basal bodies is known as the "9 + 0" pattern. This means there are 9 microtubules arranged in a circle around the periphery, and there are no microtubules in the center.

4. **Triplet Structure**: Each of the 9 microtubules in the basal body is actually a triplet, consisting of three microtubules designated as A, B, and C. This triplet structure is found at the proximal end of the basal body.

5. **Conclusion**: Therefore, the correct arrangement of microtubules in basal bodies is "9 triplets in a circle" or "9 + 0" arrangement.

### Final Answer:
The arrangement of microtubules in basal bodies is "9 triplets in a circle" (9 + 0 arrangement).

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