AFAA Personal Trainer Certification Practice Exam

Which muscle type contracts without conscious control and is found in internal organs?

1. Skeletal muscle

2. Cardiac muscle

3. Smooth muscle

4. Voluntary muscle

The correct answer is: Smooth muscle

Smooth muscle is the correct choice because it is the type of muscle that operates without conscious control and is primarily located in the walls of internal organs, such as the intestines, bladder, and blood vessels. This muscle type is responsible for involuntary movements, such as the contraction of the digestive tract to move food along and the regulation of blood flow through blood vessels. Unlike skeletal muscle, which is under conscious control and is involved in voluntary movements like walking or lifting, smooth muscle functions autonomously and is regulated by the autonomic nervous system. Cardiac muscle, while also involuntary, is specific to the heart and not found in other internal organs. The term "voluntary muscle" refers to skeletal muscle, reinforcing the distinction between the muscle types based on their control mechanisms and locations.