1. Anatomy of the Urinary System
Organ System Cluster
Prepared by: Maria Michaela Valenzuela, PTRP

2. LEARNING OBJECTIVES Enumerate the organs of the urinary system.
Describe the essential gross features of each organ.
Identify the major function of each organ of the urinary system.
Determine the location of the various urinary system organs based on the regions and quadrants of the abdomen.

3. References
Seeley, R., Stephens, T., and Tate, P., Anatomy & Physiology. 8th ed. McGraw-Hill Companies, Inc..

4. Organs of the Urinary System
Kidneys
Renal Artery & Vein
Ureter
Urinary Bladder
Urethra

6. External Anatomy of the Kidneys
Bean shaped retroperitoneal structures on the posterior abdominal wall
T12 – L3
R is slightly lower than the (L)
130 g, 11 cm long, 5 cm wide

7. External Anatomy of the Kidneys
Renal capsule as covering
Perirenal fat for shock absorption
Renal fascia as anchor to abdominal wall
Renal Hilum for entry & exit of structures

9. Internal Anatomy of the Kidneys
Outer cortex
Inner medulla
Renal Sinus
Renal Pyramids
Renal Papillae
Minor & Major Calyces
Renal Pelvis

10. Cortex, renal medulla (pyramids), renal columns, renal papilla, minor calyx, major calyx, renal sinus, renal pelvis

11. Nephron
Histological & Functional unit of the kidneys

12. Nephron Renal (Bowman’s) Corpuscle Proximal Tubules Loop of Henle
Enlarged end
Proximal Tubules
Loop of Henle
Ascending & Descending
Collecting Ducts
Cortical & medullary

13. Cortical & Juxtamedullary Nephrons
85% of total nephrons
15% of total nephrons
Lie superficially
Lie near the medulla
Short loops of Henle
Long loops of henle
(-) Vasa Recta
(+) Vasa Recta

15. Glomerular Capsule Bowman’s Capsule
Extensive vascular supply from glomerular capillary bed
Layers
Parietal
Visceral layer: filtration membrane

16. Filtration Membrane Capillary Endothelium with fenestrations
Basement membrane
Foot processes of Podocytes forming filtration slits

18. Proximal Tubule Convoluted & straight part Simple cuboidal cells
Microvilli: brush border
Tight junctions
Numerous mitochondria

19. Descending Loop of Henle
Thin segment
Simple squamous epithelium
Less microvilli
Less mitochondria

20. Ascending Loop of Henle
Thick segment
Simple cuboidal epithelium
Tighter tight junctions

21. Distal tubules Simple cuboidal cells Sparse microvilli
Numerous mitochondria

22. Collecting Ducts Cortical & Medullary 2 types of cells Principal
Intercalated

24. Vascular Supply of the Kidneys
Renal Artery
Segmental artery
Interlobar artery
Arcuate Artery
Interlobular artery
Afferent Arteriole
Glomerular Capillary
Efferent Arteriole

25. Vascular Supply of the Kidneys
Peritubular Capillary
Vasa Recta
Interlobular Vein
Arcuate Vein
Interlobar Vein
Renal Vein

27. Ureters Urine flow from kidneys to the urinary bladder
Extend inferiorly & medially to obliquely enter the urinary bladder at its posterolateral surface

28. Urinary Bladder Hollow muscular container in the pelvic cavity
♀:anterior to vagina, anteroinferior to uterus
♂:anterior to rectum

29. Urinary Bladder Trigone Rugae to allow expansion
Detrussor Muscle for emptying

30. Urethra & Urinary Spincters
Urethra for exit of urine from bladder
Internal Urinary sphincter
External Urinary spincter continuous with pelvic floor

32. Thank You for Listening!