MICROANATOMY

Detailed explanation-1: -Oxygen-rich blood flows from the lungs back into the left atrium (LA), or the left upper chamber of the heart, through four pulmonary veins. Oxygen-rich blood then flows through the mitral valve (MV) into the left ventricle (LV), or the left lower chamber.

Detailed explanation-2: -In the lungs, the blood receives oxygen then leaves through the pulmonary veins. It returns to the heart and enters the left atrium. From there, blood is forced through the mitral valve into the left ventricle.

Detailed explanation-3: -Blood enters the right atrium and passes through the right ventricle. The right ventricle pumps the blood to the lungs where it becomes oxygenated. The oxygenated blood is brought back to the heart by the pulmonary veins which enter the left atrium. From the left atrium blood flows into the left ventricle.

Detailed explanation-4: -Deoxygenated blood then moves from the capillary beds through venules into the systemic veins. The systemic veins feed into the inferior and superior venae cavae, the largest veins in the body. The venae cavae flow deoxygenated blood to the right atrium of the heart.

Detailed explanation-5: -Oxygen-rich blood travels from your lungs to your left atrium through large veins called pulmonary veins.