The aorta supplies oxygenated blood from the heart's pumping chamber to the rest of the body. Pulmonary artery carries deoxygenated or unaerated blood from the heart to the lungs.Like all arteries, the pulmonary artery carries blood away from the heart.iffen › Science › Biology › Anatomy. The aorta and the pulmonary artery are the two most important arteries in the human body. The aorta is the biggest artery and channels oxygenated blood to the rest of the body. The pulmonary artery carries deoxygenated blood to the lungs for purification.