The core of a cilium or flagellum composed of microtublues and their associated proteins is called

Options

A. blepharoplast
B. axoneme
C. microfilament
D. tublin.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Structure**: Cilia and flagella are hair-like structures that extend from the surface of many eukaryotic cells. They are involved in movement and sensory functions.

2. **Composition of Cilia and Flagella**: Both cilia and flagella are primarily composed of microtubules, which are structural components made of tubulin proteins. These microtubules are arranged in a specific pattern.

3. **Core Structure**: The core structure of cilia and flagella is known as the "axoneme." The axoneme is made up of a specific arrangement of microtubules, typically in a "9+2" formation, meaning there are nine pairs of microtubules arranged in a circle around two central microtubules.

4. **Associated Proteins**: In addition to microtubules, the axoneme contains various associated proteins that help in the movement and stability of the cilia and flagella.

5. **Conclusion**: Therefore, the core of a cilium or flagellum, which is composed of microtubules and their associated proteins, is called the "axoneme."

**Final Answer**: The core of a cilium or flagellum composed of microtubules and their associated proteins is called the axoneme.

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