In human anatomy, the cortex and medulla of the kidney together form the human kidney, but in human histogenesis, the renal cortex originates from the human mesoderm and the renal medulla from the human ectoderm. Ninety percent of the substance of the human kidney is composed of the renal cortex, and the medulla accounts for 10% of the kidney. The renal cortex is the site of blood flow, which allows urine to be filtered out, produced, and discharged into the renal medulla for collection, after which it is discharged through the papillae of the medulla into the calyces and calyces, where it is collected in the renal pelvis. The renal cortex and the renal medulla also have endocrine functions. The renal medulla produces adrenaline, which regulates blood pressure in humans.