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Terms in this set (45)

•4 chambered organ with 2 superior atria and 2 inferior ventricles
•Interatrial septum divides the 2 atria
Receiving chamber
Small and thinly muscle
Atrial muscle contraction is only used to propel a small amount of blood to the ventricle below. (Most blood traveling from the atria to the ventricle does so by gravity)
•Interventricular septum divides the 2 ventricles
•Right Atrium: receives blood from 3 sources
Superior vena cava (deoxygenated blood returning from the arms, head, and upper torso)
Inferior vena cava (deoxygenated blood returning from the legs, abdomen, and pelvis)
Coronary sinus (deoxygenated blood returning from the coronary circulation)
•Passes blood to the right ventricle thru the tricuspid orifice which is associated with the tricuspid valve
•Left Atrium:
Receives oxygenated blood from the 4 pulmonary veins
Passes blood to the left ventricle via the mitral orifice which is associated with the mitral (or bicuspid) valve
Shallow depression in both sides of the interatrial septum is known as the fossa ovalis
It is a remnant of the foramen ovale, a hole in the fetal heart that allowed blood to pass from the pulmonary circuit to the systemic circuit (since the lungs are neither fully developed nor being oxygenated)
•Ventricles:
Large, muscular chambers.
Thick musculature is necessary because they are the actual "pumps."
Right ventricle discharges blood into the pulmonary trunk, the first vessel of the pulmonary circuit.
The pulmonary semilunar valve separates the right ventricle and the pulmonary trunk.
Left ventricle discharges blood into the aorta, the first vessel of the systemic circuit.
The aortic semilunar valve separates the left ventricle and the aortic trunk.
Left ventricle is larger (more muscular) than the right.
-More muscle is necessary because the left ventricle pumps blood against greater pressure (note- the right and left ventricle pump the same volume of blood per beat)