| A | B |
|---|
| myocardium | thick layer of cardiac muscle that makes up heart |
| epicardium | thin membrane attached to the myocardium; also called the visceral pericardium |
| endocardium | inner, single layer of squamous epithelium |
| atria | two upper chambers of heart |
| ventricles | two lower, more muscular chambers of heart |
| tricuspid valve | valve between right atrium and right ventricle |
| bicuspid valve (mitral valve) | located between the left atrium and left ventricle |
| pulmonary semilunar valve | valve between the right ventricle and pulmonary artery |
| aortic semilunar valve | valve between the left ventricle and aorta |
| inferior vena cava | large vein that drains the lower blood back into the heart; contains deoxygenated blood |
| superior vena cava | drains the upper bodies blood back to the heart; contains deoxygenated blood |
| right atrium | chamber the inferior and superior vena cava drain blood into |
| left atrium | chamber the pulmonary veins drain into |
| left ventricle | chamber after the left atrium; pumbs blood to the aorta |
| right ventricle | receives blood from the right atrium; pumps blood to the pulmonary artery |
| aorta | largest artery; connects the heart with the other arteries of the body |
| pulmonary circuit | carries deoxygenated blood from the right ventricle to the lungs and returns oxygenated blood to the left atrium |
| systemic circuit | carries oxygenated blood to all parts of the body except the lungs and returns deoxygenated blood to the right atrium |
| coronary arteries | branch of the aorta that supplies the heart with blood |
| cardiac veins | these vessels return the blood used by the heart back to the heart to be pumped |
| coronary sinus | openings in the right atrium in which the cardiac veins drain |
| pulmonary arteries | blood vessels that lead from the right atrium to the lungs so blood can get oxygen; contain deoxygenated blood |
| pulmonary veins | carry oxygenated blood from the lungs back to the left atrium |
| sinoatrial node | pacemaker of the heart; starts the rhythmic impulses to initiate the heartbeat; located in the right atrium |
| atrioventricular node | from the SA node the impulse goes to this structure also within the right atrium |
| A-V Bundle (bundle of His) | large fibers that branch to into right and left branches down the septum to continue to transmit the impulse |
| Purkinje fibers | branches of the A-V bundle that carry the impulse to the myocardium of the ventricles |
| pericardium | membranes that surround the heart; made of outer fibrous pericardium and inner parietal pericardium |
