Longest smooth muscles are `:-`

Options

A. Intestine
B. Stomach
C. Uterus (Pregnant)
D. Urinary bladder

Answer

To determine which organ has the longest smooth muscles among the given options, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Smooth Muscles**: Smooth muscles are involuntary muscles found in the walls of internal organs. They are responsible for various functions such as digestion, circulation, and reproduction.

2. **Identify the Options**: The options given are:
- Intestine
- Stomach
- Pregnant Uterus
- Urinary Bladder

3. **Consider the Size of Smooth Muscle Cells**: The typical size of a smooth muscle cell ranges from 20 to 50 micrometers. However, this can vary significantly in certain organs.

4. **Examine the Pregnant Uterus**: The pregnant uterus is unique because it expands significantly to accommodate a developing fetus. The size of smooth muscle cells in the pregnant uterus can range from 12 to 600 micrometers.

5. **Compare the Sizes**:
- Intestine, stomach, and urinary bladder have smooth muscle cells that do not exceed the typical range of 20 to 50 micrometers.
- The pregnant uterus, however, can have smooth muscle cells that reach up to 600 micrometers.

6. **Conclusion**: Based on the comparison, the organ with the longest smooth muscle cells is the pregnant uterus.

### Final Answer:
The longest smooth muscles are found in the **pregnant uterus**.

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