Cortex is the outer layer of an organ or other structure, as distinguished from its inner substance or medulla.
The renal cortex is the outer portion of the kidney between the renal capsule and the renal medulla. In an 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.
The renal cortex is the outer smooth, continuous layer of the kidney. The process of ultra filtration of blood is carried out in the renal cortexwhich is also known as high pressure filtration or the ultra filtration. Renal cortex is the external, outermost part of kidney and the filtration process is termed so, as this filtration can only be completed when the blood coming into the kidney through the renal artery is already carrying high pressure. Cortex consititues glomeruli in billions which are small tiny ball shaped capillaries. Every glomerulus is encircled by Bowman’s capsule. Glomeruli leak occurs in cortex during which the different components like white blood cells, red blood cells, platelets, fibrinogen staying in the blood vessels are leaked into Bowman’s capsule. The amount of this leakage is around 160 liters in every 24 hours. The liquid that is termed as ultra filtrate is mostly reabsorbed into the medulla and sent back to the blood.