First Aid for Corrections Officers Practice Test

Where is cardiac muscle found?

1. In the lungs

2. In the digestive system

3. Only in the heart

4. In both the heart and blood vessels

The correct answer is: Only in the heart

Cardiac muscle is specialized muscle tissue that is found exclusively in the heart. This type of muscle is unique because it is involuntary, meaning it operates without conscious control, and it has a striated appearance similar to skeletal muscle. The sole function of cardiac muscle is to contract and pump blood throughout the body, providing oxygen and nutrients to various organs and tissues. In contrast, cardiac muscle is not present in the lungs, the digestive system, or blood vessels. The lungs are lined with respiratory epithelium, and the digestive system consists mainly of smooth muscle, which also operates involuntarily but differs in structure and function from cardiac muscle. Blood vessels are composed of smooth muscle and connective tissue, allowing for the regulation of blood flow and pressure but not containing cardiac muscle fibers. Thus, the nature and location of cardiac muscle are distinctly tied to the heart's structure and its essential role in the circulatory system.