The result is then multiplied by cardiac output. See also maximum oxygen consumption. Pacemaker See sinoatrial node. The amount of blood in the left ventricle before contraction. Protein A molecule made up of amino acids arranged in a specific order determined by the specific message for its synthesis from a gene.
Proteins are essential for all.life processes.
Certain ones, such as the calcium pump protein and the contractile protein myosin, appear to change with age, which may account for some changes in the function of the aging heart. Sarcoplasmic reticulum A structure or organelle inside a myocyte. Its function is to store and release calcium for use during a contraction and to remove calcium after a calcium transient causes a contraction. It removes calcium more slowly with age. See calcium pump proteins.