Contractive protein are found in

Options

A. bones
B. blood
C. muscles
D. cartilage

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where contractive proteins are found. To answer this, we need to identify the type of tissue that contains these proteins.

2. **Types of Tissues**: In the animal body, there are four main types of tissues: epithelial, connective, muscular, and nervous tissues. Among these, we need to focus on which type has contractile properties.

3. **Identifying Muscular Tissue**: Muscular tissue is known for its ability to contract and relax. This property is essential for movement. There are three types of muscular tissue: skeletal, cardiac, and smooth muscles.

4. **Contractile Proteins**: The proteins responsible for the contraction of muscles are called contractile proteins. The primary contractile proteins in muscle tissue are actin and myosin.

5. **Function of Muscles**: When stimulated, muscular tissue can undergo rhythmic contractions and relaxations, which are crucial for voluntary movements (like walking and running) and involuntary movements (like the heartbeat).

6. **Conclusion**: Since contractile proteins are found in muscular tissue, the answer to the question is that contractive proteins are found in muscles.

**Final Answer**: Contractive proteins are found in muscles.

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