TeXes Science Practice Test

Which type of muscle lines the blood vessels carrying blood away from the heart?

1. Skeletal muscle

2. Smooth muscle

3. Cardiac muscle

4. Striated muscle

The correct answer is: Smooth muscle

The lining of blood vessels that carry blood away from the heart is composed of smooth muscle. This type of muscle is characterized by its involuntary control and lack of striations, which differentiates it from skeletal and cardiac muscle. Smooth muscle is essential for the regulation of blood flow and blood pressure, as it can contract and relax to modulate the diameter of the blood vessels. This contraction helps propel blood throughout the circulatory system and adjusts the flow according to the body’s needs. Skeletal muscle, on the other hand, is attached to bones and is responsible for voluntary movements, while cardiac muscle is found only in the heart and is specialized for rhythmic contractions. Striated muscle refers generally to the appearance of muscle fibers that have stripes, which includes both skeletal and cardiac muscles but does not apply to smooth muscle. Thus, smooth muscle is the correct answer, as it is specifically responsible for the function of blood vessel walls.