Give two structural characteristics of these voluntary muscles.

Explanation

### Step-by-Step Solution:

1. **Definition of Voluntary Muscles**:
- Voluntary muscles are muscles that can be controlled consciously. They are also known as skeletal muscles because they are attached to the skeleton and enable movement.

2. **First Structural Characteristic - Shape and Size**:
- The cells of voluntary muscles are very long and cylindrical in shape. This elongated structure allows for efficient contraction and movement.

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