Dear student
Renal artery is a pair of large blood vessels that branch off from the heart and enter into each kidney. The renal arteries carry a large portion of total blood flow to the kidneys and adrenal glands and ureters. The blood which they carry contains a higher percentage of oxygen.
Renal veins carry deoxygenated blood after waste products have been removed via glomerular filtration back from the kidneys to the heart.
Regards