What is troponin and where is it present?

Explanation

### Step-by-Step Solution:

1. **Definition of Troponin**: Troponin is a group of proteins that play a crucial role in muscle contraction.

2. **Location of Troponin**: Troponin is primarily found in two types of muscles:
- **Skeletal Muscles**: These are the muscles that are attached to bones and are responsible for voluntary movements.
- **Cardiac Muscles**: These are the muscles that make up the heart and are responsible for involuntary contractions that pump blood throughout the body.

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