Urinary System

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Lecture 24

• Urinary System

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Urinary System Anatomy
Anterior
Kidney
Stomach
Pancreas
Large intestine
Ureter
Liver
Abdominal aorta
Renal vein
Inferior vena cava
Renal artery
Right kidney
Renal hilum
Fibrous capsule
Spleen
Fat
Rib
Urinary bladder
Left kidney
Fig. 27.2
Urethra
Posterior
Fig. 27.1
(a) Anterior view

• External Anatomy of Kidneys
• Renal capsule
• surrounds each kidney
• Hilum
• renal artery and nerves enter and renal vein and
  ureter exit kidneys

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Internal Anatomy of Kidneys

• Renal cortex Outer area
• Renal columns
• Renal medulla Inner area
• Renal pyramids
• Calyces
• Major Converge to form renal pelvis
• Minor Collects urine from individual renal
  pyramid
• Nephron Functional unit of kidney

Fig. 27.3
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The Nephron

• Renal corpuscle
• Bowmans capsule
• Glomerulus
• network of capillaries
• Arterioles
• Afferent
• blood to glomerulus
• Efferent
• drains
• Tubules
• Proximal (convoluted) tubule
• Loops of Henle
• Descending limb
• Ascending limb
• Distal (convoluted) tubule
• Collecting ducts

Fig. 27.5
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Ureters and Urinary Bladder

• Ureters
• tubes through which urine flows from kidneys to
  urinary bladder
• Urinary bladder
• stores urine
• Urethra
• transports urine from bladder to outside of body
• difference in length between males and females
• sphincters
• Internal urinary
• External urinary

Ureter
Peritoneum
Ureteral openings
Neck of urinary bladder
Internal urethral sphincter
External urethral sphincter
Fig. 27.9
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Review Question

• Think back for a moment to the lectures on
  histology. What type of epithelium would line
  the inside of the ureters and urinary bladder?
• Stratified squamous
• Pseudostratified columnar
• Simple cuboidal
• Transitional
• Simple squamous

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Points to Remember

• Kidney filters blood to eliminate metabolic
  wastes (e.g. urea formed from ammonia that is
  removed from blood by liver) and reabsorb
  substances such as sugars, amino acids, sodium
  and chloride
• Functional unit of kidney is nephron
• Ureters, urinary bladder and urethra transport
  urine (product of nephron) outside of body

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Questions?