Muscles with characteristic striations and involuntary are

Options

A. Muscle in the wall of alimentary canal
B. Muscles of the heart
C. Muscles assisting locomotion
D. Muscles of the eyeilds

Answer

To answer the question "Muscles with characteristic striations and involuntary are," we need to analyze the options provided and understand the characteristics of different types of muscles.

### Step-by-Step Solution:

1. **Understanding Striations**:
- Striations refer to the banded appearance of certain muscle fibers. This banding is due to the arrangement of actin and myosin filaments within the muscle cells.
- Striated muscles have a striped or banded appearance.

2. **Identifying Muscle Types**:
- There are three main types of muscles in the human body:
- **Skeletal Muscle**: These are striated and voluntary, meaning we can control their movement.
- **Cardiac Muscle**: These are striated but involuntary, meaning they function without conscious control and are found only in the heart.
- **Smooth Muscle**: These are non-striated and involuntary, found in walls of hollow organs like the alimentary canal.

3. **Analyzing the Options**:
- **Muscles in the wall of the alimentary canal**: These are smooth muscles, which are non-striated and involuntary.
- **Muscles of the heart**: These are cardiac muscles, which are striated and involuntary.
- **Muscles assisting locomotion**: These are skeletal muscles, which are striated and voluntary.
- **Muscles of the eyelid**: These are also voluntary muscles and are striated.

4. **Conclusion**:
- The only type of muscle that fits the criteria of being both striated and involuntary is the **muscles of the heart**, which are cardiac muscles.

### Final Answer:
**The muscles with characteristic striations and involuntary action are the muscles of the heart.**

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