Rhythmical contraction is noticed in

Options

A. Cardiac muscles
B. Striped muscles
C. Unstriped muscles
D. In all the muscles.

Answer

**Step-by-Step Solution:**

1. **Identify the Question:** The question asks where rhythmical contraction is noticed among the given options: cardiac muscles, striped muscles, unstriped muscles, or all muscles.

2. **Analyze Cardiac Muscles:**
- Cardiac muscles are located in the walls of the heart.
- They are involuntary muscles, meaning they function without conscious control.
- Cardiac muscles exhibit rhythmic contractions to regulate the heartbeat.
- **Conclusion:** Cardiac muscles show rhythmic contraction.

3. **Analyze Striped Muscles:**
- Striped muscles, also known as skeletal muscles, are voluntary muscles.
- They can contract quickly but do not exhibit rhythmic contraction.
- **Conclusion:** Striped muscles do not show rhythmic contraction.

4. **Analyze Unstriped Muscles:**
- Unstriped muscles, also referred to as smooth muscles, are also involuntary.
- They are uncontrolled and do not show rhythmic contraction; their contractions are not regular.
- **Conclusion:** Unstriped muscles do not show rhythmic contraction.

5. **Analyze the Option "All Muscles":**
- Since only cardiac muscles exhibit rhythmic contraction, this option is incorrect.
- **Conclusion:** Not all muscles show rhythmic contraction.

6. **Final Answer:**
- Based on the analysis, the only type of muscle that shows rhythmic contraction is the cardiac muscle.

**Final Answer:** Rhythmical contraction is noticed in cardiac muscles.

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