Algonquin College Health Program Assessment (AC-HPAT) Practice Exam

What is the primary structural component of the esophagus?

1. Skeletal muscle

2. Smooth cartilage

3. Skeletal cartilage

4. Smooth muscle

The correct answer is: Smooth muscle

The primary structural component of the esophagus is smooth muscle. The esophagus is part of the digestive system and functions to transport food from the throat to the stomach. Its wall is composed of multiple layers, with the muscular layer being crucial for peristalsis, the wave-like contractions that move food along the digestive tract. Smooth muscle is involuntary, allowing the esophagus to continuously and rhythmically contract without conscious control, which is essential for effective swallowing and movement of food. The presence of smooth muscle enables the esophagus to maintain a certain degree of elasticity and strength, facilitating the passage of varied food textures without the need for reflexive action. The other options involve skeletal muscle and cartilage, which are not the primary components of the esophagus. Skeletal muscle is typically found in areas where voluntary control is necessary, such as the upper esophagus, but it does not constitute the main structure. Cartilage, meanwhile, provides structural support in other organs like the trachea but is not a component of the esophageal structure. Thus, the correct choice effectively reflects the essential role of smooth muscle in the esophagus.