Explanation: Ribs to sternum. The typical rib is joined to the sternum by its own costal cartilage. The manubrium is a portion of the sternum.
Explanation: Right atrium. The superior and inferior venae cavae enter the right atrium of the heart.
Explanation: Pulmonary. The pulmonary valve prevents blood from exiting the pulmonary artery and flowing back into the right ventricle.