Kidney Structure (Cambridge International A-Level Biology)

Structure of the Human Kidney

Spec point — 14.1.4 · describe the structure of the human kidney, limited to: • fibrous capsule • cortex • medulla • renal pelvis • ureter • branches of the renal artery and renal vein

Structure of the human kidney

• Humans have two kidneys

• The kidneys are responsible for carrying out two very important functions:

  • As an osmoregulatory organ—they regulate the water content of the blood (vital for maintaining blood pressure)
  • As an excretory organ—they excrete the toxic waste products of metabolism (such as urea) and substances in excess of requirements (such as salts)

The position of the kidneys and their associated structures

• The kidney itself is surrounded by a fairly tough outer layer known as the fibrous capsule

• Beneath the fibrous capsule, the kidney has three main areas:

  • The cortex (contains the glomerulus, Bowman’s capsule, proximal convoluted tubule, and distal convoluted tubule of the nephrons)
  • The medulla (contains the loop of Henle and collecting duct of the nephrons)
  • The renal pelvis (where the ureter joins the kidney)

A cross-section of a kidney (as seen when cut in half vertically)

Exam Hint Make sure you can identify all the structures mentioned on this page if you are presented with a diagram of the kidney and its associated structures, or a diagram with a vertical cross-section of the kidney itself.