Pulmonary - carries oxygen-depleted blood away from the heart, to the lungs, and returns oxygenated blood back to the heart. Systemic - carries oxygenated blood away from the heart to the body, and returns deoxygenated blood back to the heart.
The Aorta carries oxygenated blood from the left ventricle of the heart for delivery around the body. The Pulmonary artery carries blood from the right ventricle of the heart to the lungs for oxygenating. Hope this helps.