The next type of muscle that we're going to discuss is the cardiac muscle. Now the cardiac muscle is the muscle that makes up the heart and just like skeletal muscle is stretched because it consists of these individual units we call sarcomeres. Our cardiac muscle is also stretched because it consists of sarcomire. So if we take a look at the heart, the heart appears to be striped, it contains these triations shown in red and that's because if we zoom in onto an individual cardiac muscle cell, we contain these myofibrils that consist of sarcomeres. So basically if we take individual sarcomeres and we connect them end to end, we basically form something called a myofibril and we have many of these cylindrically shaped myofibrils in any given cardiac muscle cell. In this case, we have 123-4567 myofibrils in this particular cardiac muscle cell.