Which type of muscles show peristaltic movements in the gastrointestinal tract?

Options

A. Striated
B. Smooth
C. Cardiac
D. Skeletal

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which type of muscles are responsible for peristaltic movements in the gastrointestinal tract.

2. **Identifying Muscle Types**: There are three main types of muscles in the human body: striated (skeletal) muscles, smooth muscles, and cardiac muscles.

3. **Analyzing Striated Muscles**:
- Striated muscles, also known as skeletal muscles, are voluntary muscles.
- They are responsible for the movement of bones and are not found in the gastrointestinal tract.
- Therefore, striated muscles do not show peristaltic movements.

4. **Analyzing Smooth Muscles**:
- Smooth muscles are involuntary muscles found in various organs, including the gastrointestinal tract.
- They are responsible for peristaltic movements, which are wave-like contractions that move food through the alimentary canal.
- Thus, smooth muscles are the correct answer.

5. **Analyzing Cardiac Muscles**:
- Cardiac muscles are specialized muscles found only in the heart.
- They are responsible for pumping blood and are not involved in gastrointestinal movements.
- Hence, cardiac muscles do not show peristaltic movements.

6. **Analyzing Skeletal Muscles**:
- Skeletal muscles are another name for striated muscles and are also voluntary.
- They facilitate bodily movements but are not involved in the gastrointestinal tract.
- Therefore, skeletal muscles do not show peristaltic movements.

7. **Conclusion**: The type of muscles that show peristaltic movements in the gastrointestinal tract is smooth muscles.

**Final Answer**: Smooth muscles show peristaltic movements in the gastrointestinal tract.

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