EVERYDAY SCIENCE

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: -Explanation: The muscles of the heart are called the cardiac muscles or myocardium which is responsible for the pumping of the heart all the time. Thus, the muscle of the heart is involuntary in nature. It is striated and branched and its function is regulated by the autonomous nervous system.

Detailed explanation-3: -Cardiac muscles are said to be involuntary because they are not controlled by our will. These muscles are found in heart and are the only muscles which work throughout the life without getting tired or fatigue.

Detailed explanation-4: -Cardiac muscle, like skeletal muscle, is a striated muscle and much of the mechanism of contraction of the two muscle types is similar. Both use the proteins actin and myosin arranged in a highly organized lattice as the basis of the force-generating apparatus.

Detailed explanation-5: -Cardiac muscles are also involuntary muscles but are found only in the heart. Cardiac muscles are branched and cylindrical in shape. They are uninucleate cells.