MICROANATOMY

Detailed explanation-1: -The outer, reddish region, next to the capsule, is the renal cortex. This surrounds a darker reddish-brown region called the renal medulla . The renal medulla consists of a series of renal pyramids, which appear striated because they contain straight tubular structures and blood vessels.

Detailed explanation-2: -The renal medulla also consists of the renal columns, which are the spaces between the renal pyramids, and the renal papillae. The renal papillae refer to the tips of the renal pyramids, which collect the remainder of the filtrate that consists of waste and solutions.

Detailed explanation-3: -The medulla is divided into 8-18 conical regions, called the renal pyramids; the base of each pyramid starts at the corticomedullary border, and the apex ends in the renal papilla which merges to form the renal pelvis and then on to form the ureter.