1. Chapter 22
The Urinary System

2. Key Terms angiotensin glomerulus tubular reabsorption
antidiuretic hormone (ADH) hemodialysis urea
calculi kidne ureter
cystitis micturition urethra
dialysis nephron urinalysis
excretion osmolarity urinary bladder
glomerular filtrate pyelonephritis urine
glomerulonephritis renin

3. Systems Involved in Excretion
Urinary (excretory system)
Regulates volume, acid–base balance and electrolyte composition of body fluids
Main parts of the urinary system
Kidneys
Ureters
Urinary bladder
Urethra
Other systems that function in excretion:
Digestive
– Respiratory
– Integumentary

4. Figure 22-1 Urinary system.
Systems Involved in Excretion (cont.)
Figure 22-1 Urinary system.
Identify the structure that carries urine to and from the bladder.

5. The Kidneys (cont.) Kidney Activities Excretion Urea
Homeostasis of body fluids
Blood pressure regulation
Hormone production
Erythropoietin (EPO)

6. The Kidneys (cont.) Kidney Structure
Lie against back muscles in the upper abdomen
Right kidney lower than left to accommodate liver
Enclosed in membranous renal capsule
Adipose capsule of fat
Fascia anchors the kidney to peritoneum and abdominal wall
Retroperitoneal space
Renal blood vessels
Renal artery
Renal vein

7. The Kidneys (cont.) Kidney Structure Organization Renal pyramids
Hilum
Renal cortex (outer portion)
Renal medulla (inner portion)
Renal pyramids
Renal pelvis
Calyces

8. The Kidneys (cont.) Kidney Structure (cont.)
Nephron and its blood supply
Nephron
Glomerular (Bowman) capsule
Renal tubule
Proximal tubule
Nephron loop
Distal tubule

9. The Kidneys (cont.) Kidney Structure (cont.)
Nephron and its blood supply (cont.)
Blood supply
Glomerulus
Afferent arteriole
Efferent arteriole
Peritubular capillaries

10. The Kidneys (cont.) A nephron and its blood supply10

11. Figure 22-4 Microscopic view of the kidney.
The Kidneys (cont.)
Figure 22-4 Microscopic view of the kidney. 11

12. The Kidneys (cont.) Formation of Urine Glomerular filtration
Glomerular filtrate
Tubular reabsorption
Diffusion
Osmosis
Active transport
Tubular secretion

13. Figure 22-5 Glomerular filtration: The first step in urine formation.
The Kidneys (cont.)
Figure 22-5 Glomerular filtration: The first step in urine formation. 13

14. The Kidneys (cont.) Formation of Urine (cont.) Concentration of urine
The proximal tubule reabsorbs about 65% of filtered water by osmosis.
Juxtamedullary nephrons
Medullary osmotic gradient
Antidiuretic hormone (ADH)

15. Figure 22-6 Urine concentration.
The Kidneys (cont.)
Figure 22-6 Urine concentration. 15

16. The Kidneys (cont.) Summary of Urine Formation Glomerular filtration
Tubular reabsorption
Tubular secretion
Concentration of urine

17. Figure 22-7 Summary of urine formation in a nephron.
The Kidneys (cont.)
Figure 22-7 Summary of urine formation in a nephron.
What vessels absorb materials that leave the nephron? 17

18. The Kidneys (cont.) The Juxtaglomerular (JG) Apparatus
Specialized region of the kidney is involved in blood pressure regulation.
Distal tubule
Afferent arteriole
Triggered by low sodium content in the glomerular filtrate.
Secretes enzyme renin
Angiotensin II

19. Figure 22-8 The juxtaglomerular (JG) apparatus.
The Kidneys (cont.)
Figure 22-8 The juxtaglomerular (JG) apparatus. 19

20. Elimination of Urine (cont.)
The Ureters
Long, slender, muscular tubes
Extend from the kidney to urinary bladder
Entirely extraperitoneal
Move urine by gravity and peristalsis

21. Elimination of Urine (cont.) The Urinary Bladder
Located posterior to the pubic symphysis
Temporary reservoir for urine
Bladder wall has many layers:
Lined with mucous membrane
Rugae
Connective tissue
Involuntary muscle tissue
Parietal peritoneum
Trigone
What gland does the urethra pass through in the male?

22. Elimination of Urine (cont.)
The Urethra
Carries urine from the bladder to the outside
Differs in males and females:
Male
Approximately 20 cm in length
Serves dual purpose as part of both the reproductive and urinary systems
Female
Approximately 4 cm in length
Entirely separate from the reproductive system

23. Elimination of Urine (cont.)
Urination
Process of expelling urine from bladder (micturition)
Involuntary control
Internal urethral sphincter
Voluntary control
External urethral sphincter

24. Elimination of Urine (cont.)
The Urine
95% water, 5% dissolved solids and gases
pH averages 6.0
Specific gravity measures amount of dissolved substances
Normal range (very dilute) to (very concentrated)

25. Elimination of Urine (cont.)
The Urine (cont.)
Normal constituents of urine
Nitrogenous waste products
Urea
Uric acid
Creatinine
Electrolytes
Sodium and chloride ions
Sulfates
Phosphates
Pigments (e.g., urochrome, bile pigments, food pigments)

26. Elimination of Urine (cont.)
The Urine (cont.)
Abnormal constituents of urine
Glucose
Albumin
Blood
Ketones
White blood cells
Casts

27. Disorders of the Urinary System (cont.)
Obstructions and Structural Disorders
Hydronephrosis
Kidney stones (renal calculi)
Staghorn calculi
Renal colic
Lithotripsy (extracorporeal shock wave lithotripsy)
Structural abnormalities
Renal hypoplasia
Renal dysplasia
Ureteral stricture
Ureterocele
Hypospadias

28. Disorders of the Urinary System (cont.)
Figure Kidney stones.
What does the word extracorporeal mean? 28

29. Disorders of the Urinary System (cont.)
Figure Hypospadias. 29

30. Disorders of the Urinary System (cont.)
Inflammatory Disorders
Urinary tract infection (UTI)
Urethritis
Cystitis
Interstitial cystitis
Pyelonephritis
Glomerulonephritis

31. Disorders of the Urinary System (cont.)
Neoplasms
Bladder tumors
Symptoms
Hematuria
Frequent urination
Causes
Toxins
Heavy cigarette smoking
Presence of urinary stones
Treatment
Tumor removal
Localized chemotherapy
Cystectomy
Ileal conduit

32. Disorders of the Urinary System (cont.)
Figure Cystoscopy. 32

33. Disorders of the Urinary System (cont.)
Figure Ureterocele. 33

34. Disorders of the Urinary System (cont.)
Figure Ileal conduit. 34

35. Disorders of the Urinary System (cont.)
Polycystic Kidney Disease
Genetic disorder
Usually asymptomatic in children
Destruction of nephrons as disease progresses resulting in chronic renal failure
Treatment:
Renal dialysis
Kidney transplantation

36. Disorders of the Urinary System (cont.)
Renal Failure
Renal insufficiency
Acute renal failure
Causes for acute renal failure
Medical or surgical emergencies
Toxins that damage the renal tubules
Symptoms
Sudden serious decrease in kidney function
Electrolyte imbalance
Acid–base imbalance

37. Disorders of the Urinary System (cont.)
Renal Failure (cont.)
Chronic renal failure
Causes for chronic renal failure
Gradual loss of nephrons
Symptoms
Dehydration
Edema
Electrolyte imbalance
Hypertension
Anemia
Uremia

38. Disorders of the Urinary System (cont.)
Renal Failure (cont.)
Renal dialysis and kidney transplantation
Dialysis
Hemodialysis
Peritoneal dialysis
Kidney transplantation
Final option for treatment of kidney failure

39. Disorders of the Urinary System- Dialysis39

40. Disorders of the Urinary System (cont.)
Urinary Incontinence
Causes
Neurologic disorder
Trauma to the spinal cord
Weakness of the pelvic muscles
Impaired bladder function
Medications
Types of urinary incontinence
Stress incontinence
Urge incontinence (overactive bladder)
Overflow incontinence
Enuresis

41. The Effects of Aging on the Urinary System
Loss of the kidney’s ability to concentrate urine
Decrease in number and size of nephrons
Increase in blood urea nitrogen (BUN)
Urinary infections
Prostate enlargement
Decreased bladder capacity
Incontinence

42. Case Study (cont.) Urinary Obstruction
Symptoms of benign prostatic hypertrophy
Urinary urgency and frequency
Hesitation in starting stream
Decreased urine volume
Diminished force of stream
Incomplete emptying of bladder 42

43. Case Study (cont.) Urinary Obstruction (cont.) Diagnosis Digital exam
Cystoscopy
Intravenous pyelogram results:
Hydroureter (from back pressure of urine)
Hydronephrosis (from back pressure of urine)
Treatment
Transurethral prostatectomy 43

44. Word Anatomy (cont.) Word Part Meaning Example The Kidneys juxta-
next to
The juxtaglomerular apparatus is next to the glomerulus.
nephr/o
kidney
The nephron is the functional unit of the kidney.
ren/o
The renal artery carries blood to the kidney.
retro-
backward, behind
The retroperitoneal space is posterior to the peritoneal cavity.
The Ureters
extra-
beyond, outside of
The ureters are extraperitoneal.

45. Word Anatomy (cont.) Word Part Meaning Example
Disorders of the Urinary System
-cele
swelling, enlarged space
A ureterocele is formed as the end of the ureter bulges into the bladder.
cyst/o
sac, bladder
A polycystic kidney develops many fluid-containing sacs.
dia-
through
Dialysis is the separation (-lysis) of molecules based on their ability to pass through a semipermeable membrane.
pyel/o
renal pelvis
Pyelonephritis is inflammation of the nephrons and renal pelvis.
trans-
across, through
A transurethral route is through the urethra.
The Effects of Aging
noct/i
night
Nocturia is excessive urination at night.