1. CHAPTER 25
The Urinary System
PART A

2. Learning objectives
Recognize and name the organs of urinary system according to their location in the abdominal and pelvic cavity(ILO .(ILO 1.1)
Define the terms related to urinary system.(1.2)
Recognize and contrast histology of different parts of nephron.(ILO 2.1)
Label the anatomical and histological features of urinary system in the activity sheets(ILO 2.2)

3. Lecture outlines Urinary System Organs Kidney Anatomy Nephron
External
Internal
Nephron
Parts of nephron

4. Urinary System Organs
Kidneys
Ureters
Urinary bladder
Urethra

5. Urinary System Organs Kidneys are major excretory organs
Ureters transport urine from the kidneys to the bladder
Urinary bladder is the temporary storage reservoir for urine
Urethra transports urine out of the body

6. Hepatic veins (cut) Esophagus (cut) Inferior vena cava Renal artery
Adrenal gland
Renal hilum
Aorta
Renal vein
Kidney
Iliac crest
Ureter
Rectum (cut)
Uterus (part
of female
reproductive
system)
Urinary
bladder
Urethra
Figure 25.1

7. External anatomy of Kidney Anatomy
Retroperitoneal, in the superior lumbar region
Right kidney is lower than the left
Convex lateral surface, concave medial surface

8. Anterior Inferior vena cava Aorta Peritoneal cavity (organs removed)
Peritoneum
Supportive
tissue layers
Renal
vein
• Renal fascia
anterior
posterior
Renal
artery
• Perirenal
fat capsule
Body of
vertebra L2
• Fibrous
capsule
Body wall
(a)
Posterior
Figure 25.2a

9. External anatomy of Kidney Anatomy
Renal hilum on the medial surface --Ureters, renal blood vessels, lymphatics, and nerves enter and exit at the hilum

10. External anatomy of Kidney Anatomy

11. Internal Anatomy of kidney
Renal cortex
A granular superficial region
Renal medulla
The cone-shaped medullary (renal) pyramids separated by renal columns

12. Internal Anatomy of kidney
Papilla
Tip of pyramid; releases urine into minor calyx
Renal pelvis
The funnel-shaped tube within the renal sinus

13. Internal Anatomy of kidney
Major calyces
The branching channels of the renal pelvis that
Collect urine from minor calyces
Empty urine into the pelvis
Urine flows from the pelvis to ureter

15. (a) Photograph of right kidney, frontal section (b) Diagrammatic view
Renal
hilum
Renal cortex
Renal medulla
Major calyx
Papilla of
pyramid
Renal pelvis
Minor calyx
Ureter
Renal pyramid
in renal medulla
Renal column
Fibrous capsule
(a) Photograph of right kidney, frontal section
(b) Diagrammatic view
Figure 25.3

16. Nephrons Structural and functional unit of the kidney that form urine
Up to 1 million nephrons per kidney
Two main parts
Renal corpuscle (cortex)
Renal tubule (cortex  medulla)

17. Parts of nephron Bowman’s capsule Glomerulus
Proximal convoluted tubule
Loop of Henle
Distal convoluted tubule
Collecting tubule

18. Figure 25.5

19. Figure 25.5 Renal cortex Renal medulla Renal corpuscle Renal pelvis
Glomerular capsule: parietal layer
Renal cortex
Basement
membrane
Renal medulla
Renal corpuscle
Podocyte
Renal pelvis
• Glomerular capsule
Fenestrated
endothelium
of the glomerulus
• Glomerulus
Distal
convoluted
tubule
Ureter
Glomerular capsule: visceral layer
Kidney
Microvilli
Mitochondria
Proximal
convoluted
tubule
Highly infolded plasma
membrane
Cortex
Proximal convoluted tubule cells
Medulla
Thick segment
Distal convoluted tubule cells
Thin segment
Loop of Henle
• Descending limb
• Ascending limb
Collecting
duct
Loop of Henle (thin-segment) cells
Principal cell
Intercalated cell
Collecting duct cells
Figure 25.5