AP BIOLOGY

Detailed explanation-1: -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. In the lungs, the blood receives oxygen then leaves through the pulmonary veins.

Detailed explanation-2: -Your pulmonary arteries carry oxygen-poor blood from your heart to your lungs. This is a vital function. Your blood needs to reach your lungs to gain oxygen and get rid of waste products like carbon dioxide. This blood then returns to your heart, and your heart pumps it out to the rest of your body.

Detailed explanation-3: -The pulmonary artery is a big artery that comes from the heart. It splits into two main branches, and brings blood from the heart to the lungs. At the lungs, the blood picks up oxygen and drops off carbon dioxide. The blood then returns to the heart through the pulmonary veins.

Detailed explanation-4: -Blood Flow: Step by Step The blood first enters the right atrium. The blood then flows through the tricuspid valve into the right ventricle. When the heart beats, the ventricle pushes blood through the pulmonic valve into the pulmonary artery. The pulmonary artery carries blood to the lungs where it “picks up” oxygen.