Anatomy of the Heart

The heart tissue (myocardium) is made up of a variety of cells that work together to cause the heart to contract regularly. Specialized cells make up the heart's electrical (conduction) system. This system produces electrical impulses that transmit these impulses to the heart muscle fibers (myocytes), which in turn cause mechanical contraction. How to connect them is end-to-end. These thicknesses are thickened areas of the cell membrane (sarcoma) that help transfer mechanical force between cells. Sarcolem acts similarly to other cell membranes. These include maintaining an ionic gradient, emitting electrical impulses, and creating a receptor to receive hormonal and nerve stimulation. Myocytes are made up of many organelles that provide the energy needed for contraction, a large network of intracellular tubules called sarcoplasmic reticulum, which act as the main reservoir of intracellular calcium, and myofibrils, which are the constituent elements of the cell. Each myofibril is made up of repetitive units called their regulatory sarcomeroproteins, troponin and tropomyosin, with the actin and myosin filaments stacked on top of each other.