ACE Personal Trainer Practice Exam

Which of the following is NOT one of the three types of muscle?

1. Skeletal muscle

2. Cardiac muscle

3. Longitudinal muscle

4. Smooth muscle

The correct answer is: Longitudinal muscle

The correct answer pertains to the classification of muscle types found in the human body. Skeletal muscle, cardiac muscle, and smooth muscle are the three recognized types of muscle tissue. Skeletal muscle, which is under voluntary control, is primarily responsible for movement and is attached to bones. Cardiac muscle is involuntary and makes up the heart, responsible for pumping blood throughout the body. Smooth muscle, also involuntary, is found in the walls of hollow organs like the intestines and blood vessels. Longitudinal muscle, on the other hand, is not classified as one of the primary muscle types. It refers to a specific arrangement of smooth muscle fibers, often found in certain structures but does not represent a distinct category of muscle tissue like the others. This is why the selection of longitudinal muscle indicates that it does not belong to the three main types of muscle recognized in human physiology.