Where is nexin found ?

Explanation

**Step-by-Step Solution:**

1. **Understanding Nexin**: Nexin is a type of protein that plays a crucial role in the structure of cilia and flagella. It is specifically known as an inter doublet link protein.

2. **Function of Nexin**: The primary function of nexin is to maintain the 9-fold configuration of microtubules in cilia and flagella. This configuration is essential for the proper functioning and movement of these cellular structures.

3. **Location of Nexin**: Nexin is found in the inter doublet links of cilia and flagella. These are the connections between the doublet microtubules that make up the axoneme, the core structure of cilia and flagella.

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