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upper chamber of the heart that receives and holds blood that is about to enter the ventricle


a chamber of the heart that receives blood from an atrium and pumps it to the arteries


flap of tissue in the heart that prevents blood from flowing in the wrong direction


a blood vessel that carries blood from the heart to the body


any of the minute blood vessels connecting arterioles with venules


a blood vessel that carries blood from the capillaries toward the heart


the large trunk artery that carries blood from the left ventricle of the heart to branch arteries

coronary artery

the artery that branches from the aorta to supply blood to the heart


process by which molecules tend to move from an area where they are more concentrated to an area where they are less concentrated

blood pressure

the pressure of the circulating blood against the walls of the blood vessels


colorless watery fluid of blood and lymph containing no cells and in which erythrocytes and leukocytes and platelets are suspended


a hemoprotein composed of globin and heme that gives red blood cells their characteristic color


a cell fragment that plays an important part in forming blood clots

lymphatic system

the interconnected system of spaces and vessels between body tissues and organs by which lymph circulates throughout the body


condition in which fatty deposits called plaque build up on the inner walls of the arteries


a common disorder in which blood pressure remains abnormally high (a reading of 140/90 mm Hg or greater)

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