Anatomy of the Kidneys

Location and Structure

• **Kidneys' Position:

  • Situated below the diaphragm in the abdominal region.
  • Right and left kidneys with adrenal (suprarenal) glands above them.
  • Abdominal aorta runs close to the kidneys.

• **Kidney's Shape:

  • Shaped like a kidney bean.
  • Renal hilum: Entry/exit point for vessels and ureter.

Key Components

• Adrenal Glands:

  • Located at the top of each kidney.
  • Produces important hormones.

• **Renal Hilum:

  • Contains the renal vein, renal artery, and the ureter.

Blood Supply and Excretion

• **Renal Artery and Vein:

  • Delivers blood to and from the kidney.

• **Ureter:

  • Transports urine from the kidney to the bladder.
  • Positioned posteriorly to the renal artery and vein.

Internal Structure

• **Renal Capsule (Fibrous Capsule):

  • Outer protective layer of the kidney.

• **Renal Cortex:

  • Outer region of the kidney.

• **Renal Medulla:

  • Inner region containing:
    • Renal (Medullary) Pyramids: Darker, triangular regions.
    • Renal Columns or Cortical Columns: Spaces between the pyramids.

• **Renal Papilla:

  • Tips of the renal pyramids.
  • Urine is funneled into the minor calyx.

• **Calyces:

  • Minor Calyx:
    • Collects urine from the renal papilla.
  • Major Calyx:
    • Collects urine from minor calices.
    • Directs urine to the renal pelvis.
  • **Renal Pelvis:
    • Funnel-shaped structure leading to the ureter.

Urinary Pathway

• Urine flow sequence:
  1. Renal Papilla.
  2. Minor Calyx.
  3. Major Calyx.
  4. Renal Pelvis.
  5. Ureter.
  6. Bladder.
  7. Urethra.

Identifying Anterior vs. Posterior

• **Renal Hilum Orientation:
  • Ureter entrance indicates posterior side.
  • Renal artery and vein lie anterior to the ureter.