Book 4 - Self Instructional Manual for Cancer Registrars - SEER ...

SECTION HTHE URINARY SYSTEMThe urinary system in both males and females consists of two kidneys, two ureters, a urinarybladder, and a urethra. It is part of the excretory system of the body which also includes therespiratory, integumentary, and digestive systems.KidneyEach kidney is located lateral to the spinal column in the lumbar region behind the abdominalcavity. Each is, therefore, retroperitoneal, or in back of the peritoneal cavity. Each is embedded ina mass of fatty tissue which is surrounded by a fibrous covering called the renal fascia or Gerota'sfascia. The renal pelvis represents extensions of the ureter and the kidney parenchyma 1 at the hiluswhich is located on the inner, or medial side of each kidney. The structures of the kidneyparenchyma and kidney pelvis are quite different:• The kidney parenchyma is the glandular part of the organ where the filtration ofblood takes place and urine is produced. The outer connective tissue layer iscalled the cortex; the inner structure is called the medulla. The medulla consistsof renal (medullary) pyramids which are separated from one another by extensionsof the cortex into the medulla called renal columns.• The renal pelvis and calyces2 collect the urine which is then transported by theureters from the kidney to the urinary bladder for storage.Figure 40. KIDNEYCortexP.renchy-- __ _''duL]L"!1.lparenchyma--the functional working elements of an organ.2calyces--(plural of calyx--cuplike organs or cavities.243