Kaplan Nursing Entrance Practice Exam

Which characteristic is true for smooth muscle?

1. It is voluntary

2. It is striated

3. It is present in the gastrointestinal tract

4. It is found only in the heart

The correct answer is: It is present in the gastrointestinal tract

Smooth muscle is indeed characterized by its presence in the gastrointestinal tract. It plays a vital role in the digestion process as it is responsible for the involuntary movements that propel food through the digestive system. This muscle type is non-striated, which distinguishes it from skeletal and cardiac muscle. The smooth muscle's involuntary nature allows it to function automatically, controlling processes such as peristalsis without conscious thought. The other characteristics mentioned do not align with the properties of smooth muscle. For example, smooth muscle is not voluntary, making the first option inaccurate. The second option, referring to striated muscle, mistakenly applies this feature, which is characteristic of skeletal and cardiac muscle, not smooth muscle. Lastly, smooth muscle is not exclusive to the heart; that function is performed by cardiac muscle specifically. Thus, the presence of smooth muscle in the gastrointestinal tract highlights its essential role in the body's functionality, confirming the accuracy of the correct answer.