THORAX ABDOMEN AND PELVIS

Detailed explanation-1: -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.

Detailed explanation-2: -Carbon dioxide moves from the cells and into the capillaries. Blood leaves the capillary and enters the small venules. These venules become progressively larger vessels called veins. The vena cava are the two largest veins that carry blood into the right upper chamber of the heart (the right atrium).

Detailed explanation-3: -The superior vena cava carries blood from the head, neck, arms, and chest. The inferior vena cava carries blood from the legs, feet, and organs in the abdomen and pelvis.