MICROANATOMY

Detailed explanation-1: -Cardiac muscle, like skeletal muscle, is made up of sarcomeres that allow for contractility. However, unlike skeletal muscle, cardiac muscle is under involuntary control. The cardiac muscle is responsible for the contractility of the heart and, therefore, the pumping action.

Detailed explanation-2: -The circulatory system helps the muscular system by pumping blood and oxygen to the working muscles. The circulatory system also helps the muscular system because it allows muscles to receive the oxygen they need to function properly.

Detailed explanation-3: -Myocardial contraction occurs at the myofibrillar level by regulated interactions between actin and myosin. Cardiac troponins (cTns) serve various roles in such regulation, including troponin C (cTnC) in calcium binding, troponin I (cTnI) in inhibition, and troponin T (cTnT) in tropomyosin binding.

Detailed explanation-4: -The cardiac muscle is the muscle of the heart.