<Tr> <Th> FMA </Th> <Td> 15581 </Td> </Tr> <Tr> <Td_colspan="2"> Anatomical terminology (edit on Wikidata) </Td> </Tr> <P> The renal cortex is the outer portion of the kidney between the renal capsule and the renal medulla . In the adult, it forms a continuous smooth outer zone with a number of projections (cortical columns) that extend down between the pyramids . It contains the renal corpuscles and the renal tubules except for parts of the loop of Henle which descend into the renal medulla . It also contains blood vessels and cortical collecting ducts . </P> <P> The renal cortex is the part of the kidney where ultrafiltration occurs . Erythropoietin is produced in the renal cortex . </P>

What is the difference in function between the renal cortex and the renal medulla
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