ANATOMY

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: -The left atrium receives oxygen-rich blood from the lungs and pumps it to the left ventricle.

Detailed explanation-3: -Normally, each pulmonary vein connects directly with your left atrium. In that case, there are four ostia (openings) in your left atrium, one for each of your pulmonary veins. Oxygen-rich blood travels through these openings and into your left atrium.

Detailed explanation-4: -A typical heart has two upper and two lower chambers. The upper chambers-the right and left atria-receive incoming blood. The lower chambers-the right and left ventricles-pump blood out of your heart.

Detailed explanation-5: -Your heart has a right and left side separated by a wall called the septum. On each side of the wall, there is a small collecting chamber called an ‘atrium’, which leads into a large pumping chamber called a ‘ventricle’.