From the right ventricle the blood flows into the pulmonary artery or pulmonary trunk through another one-way valve.  This valve has three names.  The first is the right semilunar valve because it is found on the right hand side.  The second is the pulmonary semilunar valve because the blood is flowing towards the lungs.  The third is simply the pulmonary valve.  The blood will go through this valve into the Pulmonary ARTERY.  Notice that this artery is carrying deoxygenated blood.  Arteries and veins are NOT defined by the amount of oxygen they carry, but by the direction of the flow of the bloodArteries carry blood Away from the heart and veins carry blood towards the heart.

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