APPLIED RADIOLOGICAL ANATOMY

Detailed explanation-1: -Cardiac muscle cells are located in the walls of the heart, appear striped (striated), and are under involuntary control. Smooth muscle fibers are located in walls of hollow visceral organs (such as the liver, pancreas, and intestines), except the heart, appear spindle-shaped, and are also under involuntary control.

Detailed explanation-2: -At a cellular level, smooth muscle functions as an involuntary non-striated muscle. Smooth muscle contains thick and thin filaments that do not arrange into sarcomeres, resulting in a non-striated pattern.

Detailed explanation-3: -These involuntary muscles include smooth muscles and cardiac muscles.

Detailed explanation-4: -Smooth muscle, found in the walls of the hollow internal organs such as blood vessels, the gastrointestinal tract, bladder, and uterus, is under control of the autonomic nervous system. Smooth muscle cannot be controlled consciously and thus acts involuntarily.