Final answer:
The visible tissue structures within the medulla of the kidney are called renal pyramids. These cone-shaped tissues are part of the medulla and process urine within the kidney. Each nephron starts in the renal cortex with the Bowman's capsule and continues with a renal tubule.
Step-by-step explanation:
The visible tissue structures within the medulla of the kidney are known as renal pyramids. These are cone-shaped tissues that are involved in the processing of urine. Each renal pyramid ends in a structure known as the renal papilla, which points toward the renal pelvis, leading to the ureter on the outside of the kidney.
The renal pyramids are a part of the medulla, which is one of the three main internal regions of the kidney - the outer cortex, a middle medulla, and the renal pelvis. The renal cortex, which is granular in appearance, contains the nephrons, which are the functional units of the kidney. Each nephron begins with a structure called the Bowman's capsule, containing a capillary network known as the glomerulus, and continues with a renal tubule that processes the filtrate into urine.