The urinary system consists of the kidneys, ureters, urinary bladder, and urethra. The kidneys filter waste from the blood and regulate fluid balance and electrolyte levels. The ureters carry urine from the kidneys to the bladder. The bladder stores urine until urination. The urethra then carries urine out of the body. The urinary system maintains blood pressure, produces erythropoietin and vitamin D, and removes wastes and toxins from the blood. Diseases can include acute renal failure, glomerulonephritis, and kidney stones.

1. URINARY SYSTEM
Group 3

2. Urinary System
• Maintains the balance of products of ammonia such as sodium
ions, chloride, potassium, hydrogen, sulfate and phosphate.
• Excretes body wastes
• Consists of :
 2 kidneys
 2 ureters
 1 urinary bladder
 Urethra

3. Functions
• Excretion: kidneys filter large amounts of fluid from the blood
and eliminate nitrogenous waste, drugs and toxins
• Maintain blood volume and concentration: kidneys control
blood volume by regulating the proper balance in the blood
between salts and water
- regulate the volume of urine produced
- regulate the concentration of ions in body fluids and blood
so the proper balance of sodium, chloride, potassium, calcium
and phosphate ions is maintained.

4. Functions
• pH regulation: kidneys control the proper balance of hydrogen
ions in the blood
• Blood pressure: kidneys produce a enzyme “RENIN” that helps
adjust the filtration pressure
• Erythrocyte concentration: kidneys produce “ERYTHROPOIETIM” a
hormone that stimulates red blood cell production

5. Functions
• Release of Prostaglandin:
- prostaglandin dilate kidney blood vessels
- dilated blood vessels contribute to homeostatis by
maintaining blood flow in the kidney
• Vitamin D production: kidneys convert vit.D to its active form,
Calciferol
- Together with liver and skin, it participates in Vitamin D
synthesis

6. Kidney
• Paired , bean shaped organ that lie on either
side of the vertebral column below the
diaphragm and liver
• Regulate the composition and volume of the
blood
• Remove wastes from the blood in the form of
urine

7. Ureters
• tubes made of smooth muscle
fibers that propel urine from
the kidneys to the urinary
bladder
• Extension of the kidney pelvis
• Ureters join the bladder via a
tunnel in the bladder wall,
which is angled to prevent
reflux (backflow) of urine into
the ureters when the bladder
muscle contracts.

8. Urinary Bladder
• organ that
collects urine excreted by
the kidneys before disposal
by urination.
• hollow muscular, and
distensible or elastic organ
• When the bladder is
stretched, this signals
the parasympathetic nervous
system to contract
the detrusor muscle. This
encourages the bladder to
expel urine through the
urethra.

9. Urethra
• tube that connects the urinary bladder to the genitals for the
removal of fluids out of the body
• In males, the urethra travels through the penis, and
carries semen as well as urine.
• In females, the urethra is shorter and emerges above the vaginal
opening.
• Women use their urethra only for urinating, but men use their
urethra for both urinating and ejaculating.
• The external urethral sphincter is a striated muscle that allows
voluntary control over urination.

10. Diseases of the
Urinary System

11. • Acute Renal Failure
- decrease in the ability of the kidney to excrete wastes and regulate the
homeostasis of blood volume, pH, etc.
• Glomerulonephritis
- inflammation of the glumeroli
- involvement of person’s own antibodies

12. • Kidney stones
- also known as a renal calculus
- solid concretion or crystal aggregation formed in the kidneys
from dietary minerals in the urine
-typically classified by their location:
 in the kidney - nephrolithiasis
 ureter- ureterolithiasis
 bladder- cystolithiasis
 by their chemical composition- calcium containing