Asters are formed from .............

Explanation

### Step-by-Step Solution:

1. **Understanding Asters**: Asters are star-shaped structures that are formed during cell division, particularly during mitosis in animal cells.

2. **Components of Asters**: Asters consist of a centrosome and its associated microtubules. The centrosome is a key structure in the cell that plays a crucial role in organizing microtubules.

3. **Role of Centrioles**: The centrosome is made up of two centrioles. These centrioles are cylindrical structures that are essential for the formation of the spindle fibers during cell division.

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