Write true or false
Cardiac muscles undergo rhythmic contraction and relaxation throughout life.

Answer

To determine whether the statement "Cardiac muscles undergo rhythmic contraction and relaxation throughout life" is true or false, we can break it down step by step.

### Step-by-Step Solution:

1. **Understanding Cardiac Muscles**:
- Cardiac muscles are specialized muscles found in the heart. They are responsible for pumping blood throughout the body.

2. **Nature of Cardiac Muscle Contraction**:
- Cardiac muscles are known for their ability to contract and relax rhythmically. This rhythmic action is essential for maintaining a consistent heartbeat.

3. **Lifespan of Cardiac Muscle Activity**:
- The heart continues to beat throughout a person's life, from the time of embryonic development until death. This means that cardiac muscles are active continuously and rhythmically throughout life.

4. **Involuntary Control**:
- Cardiac muscles operate involuntarily, meaning they function without conscious control. This is crucial for their role in sustaining life.

5. **Conclusion**:
- Since cardiac muscles do indeed undergo rhythmic contraction and relaxation throughout life, the statement is true.

### Final Answer:
**True**

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