Cardiac Muscle Fiber. Cardiac muscles are found in the heart and they contract to pump blood. In both skeletal and cardiac muscle these sarcomeres are made of actin and myosin and are supported by the same proteins.
Cardiac Muscle Wikipedia from en.wikipedia.org
Cardiac muscle fibers have their own rhythm. The phosphorylation and dephosphorylation of phospholamban which comprises 3-4 of the SR membrane protein regulate the Ca 2 -ATPase activity in the SR membrane. Purkinje fibers are easily seen on the lower internal surface of this section through the ventricular wall.
The route for conducting AP throughout the heart muscles.
Cardiac muscle fibers are long branched cells shaped like cylinders joined end-to-end with one or two nuclei located centrally. Initiates the heart beat and helps spread the impulse reapidly. Cardiac muscle fibers have their own rhythm. Each Myofibril is constructed of a series of sacromeres aligned end to end along its length.
