Lecture Notes: The Role and Function of Kidneys

Key Points

• Kidneys hold 22% of blood supply
  • Approximately 1.1 liters of blood flow through kidneys per minute.
  • All blood in the body is filtered every 5 minutes.

Overview of Kidney Function

• Blood Flow through Kidneys
  • Blood enters through the renal artery.
  • Filtered blood exits via renal veins.
  • Urine is produced and exits through the ureters.

Importance of Kidneys

• Regulation of Blood Components
  • Maintenance of blood pH and osmolality.
  • Excretion of waste products.

Detailed Kidney Function

• Filtration and Collection Functions

  • Filtration: Removal of waste and essential molecules (ions, amino acids, glucose).
  • Collection: Disposing waste and forming urine.

• Functional Unit: The Nephron

  • Responsible for filtration and collection.
  • Located between renal cortex (outer shell) and renal medulla (inner part).

Kidney Anatomy

• Renal Cortex and Medulla

  • Cortex: Outer part of the kidney.
  • Medulla: Inner part of the kidney.

• Renal Calyx and Pelvis

  • Renal Calyx: Initial urine collection point.
  • Renal Pelvis: Collection area for urine from calyces.

• Ureter

  • Tube carrying urine away from kidneys.

• Renal Hilum

  • Area where renal artery, vein, and ureter emerge.

Physiological Importance

• Homeostasis

  • Maintains conditions like blood pH and blood pressure.
  • Balances salt intake and waste excretion.

• Excretion of Waste

  • Removal of urea and other waste products.

Conclusion

• Critical Role of Kidneys
  • Essential for filtering blood and maintaining body homeostasis.
  • Protects from imbalances in pH, pressure, and waste accumulation.

Future Topics

• Further discussion on nephron structures and waste management in upcoming videos.