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

Options

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

Explanation

To answer the question about the core of a cilium or flagellum composed of microtubules and their associated proteins, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Cilia and Flagella**:
- Cilia and flagella are hair-like structures found on the surface of eukaryotic cells. They play a crucial role in cell motility, which is the ability of the cell to move.

2. **Identifying the Core Structure**:
- The core of cilia and flagella is specifically composed of microtubules and associated proteins. This core structure is essential for their function.

3. **Defining the Core**:
- The core of cilia and flagella is known as the **axoneme**. The axoneme is the structural framework that supports the movement of these organelles.

4. **Composition of the Axoneme**:
- The axoneme is organized in a specific arrangement known as the "9 + 2" structure. This means there are 9 pairs of microtubules arranged in a circle around 2 central microtubules.

5. **Microtubules Composition**:
- Microtubules are made up of tubulin proteins, specifically alpha and beta tubulin subunits that polymerize to form the microtubule structure.

6. **Conclusion**:
- Therefore, the correct answer to the question is that the core of a cilium or flagellum 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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