MICROANATOMY

Detailed explanation-1: -Oxygen-poor blood from the body enters your heart through two large veins called the superior and inferior vena cava. The blood enters the heart’s right atrium and is pumped to your right ventricle, which in turn pumps the blood to your lungs.

Detailed explanation-2: -Oxygen-poor blood returns from the body to the heart through the superior vena cava (SVC) and inferior vena cava (IVC), the two main veins that bring blood back to the heart. The oxygen-poor blood enters the right atrium (RA), or the right upper chamber of the heart.

Detailed explanation-3: -Blood first enters the heart’s right atrium. A muscle contraction forces the blood through the tricuspid valve into the right ventricle. When the right ventricle contracts, blood is forced through the pulmonary semilunar valve into the pulmonary artery. Then it travels to the lungs.