2. Urinary system

4. Kidneys filter blood to keep it pure  Toxins  Metabolic wastes  Excess water Dispose of nitrogenous wastes from blood  Urea  Uric acid  Creatinine  Regulate the balance of water & electrolytes &acids and bases

5. 1.Primary organs of the urinary system 2.Located between the 12 th thoracic and 3 rd lumbar vertebrae. Right is usually lower due to liver. 3.Lie in shallow depressions against the posterior abdominal wall 4.Held in place by connective tissue [renal fascia] and surrounded by thick layer of adipose [perirenal fat]

6. Structure of the Urinary system Paired kidneys A ureter for each kidney Urinary bladder Urethra

7. About 1% of total body weight. Main structures of the kidney: 1.Renal cortex 2.Renal medulla 3.Renal pelvis 4.Nephrons_____ is the functional unit of the kidney where urine forms

8. 1.Excretion of waste products from the body. 2.Elimination of foreign substances. 3.Regulation of the amount of water in the body. 4.Regulate blood pressure. 5.Secrete erythropoietin. 6.Help activate vitamin D.

9.  The wall of the ureter consists of three layers:  The outermost is a fibrous coat,  The middle layer is muscular [ circular & longitudinal]  The innermost layer is called the mucosa, a transitional epithelium that is continuous with the lining of the renal pelvis and bladder, also secretes a protective mucus Function :- Each ureter is about 25 cm long and carries urine from the renal pelvis to the urinary bladder via peristaltic waves.

10.  Smooth, muscular sac  It lies retroperitoneally on the pelvic floor posterior to the pubic symphysis The bladder wall has three layers 1.Transitional epithelial mucosa 2.A thick muscular layer 3.A fibrous adventitia 4.Males : prostate gland surrounds the neck inferiorly 5.Females : anterior to the vagina and uterus

11. 1)stores urine 2)The bladder is distensible and collapses when empty 3)As urine accumulates, the bladder expands without significant rise in internal pressure

13. Muscular tube that: Drains urine from the bladder to the outside of the body Sphincters keep the urethra closed when urine is not being passed. There are two  Internal urethral sphincter : involuntary control  External urethral sphincter : voluntary control.

14. The female urethra is tightly bound to the anterior vaginal wall Its external opening lies anterior to the vaginal opening and posterior to the clitoris Females 3-4 cm

15. The male urethra has three regions: 1.prostatic urethra 2.membranous urethra 3.penile urethra. males 20 cm

16. 1. pH  range 4.5-8 average 6.0  vegetarian diet: urine is alkaline  protein rich diet: urine is Acidic 2. Specific gravity Ranges from 1.001 to 1.035 Urine is about 95% water. Contains urea and uric acid Normally, 1-2 liters of urine per day 3. Odor  normal is ammonia-like  diabetes mellitus- smells fruity or acetone like due to elevated ketone levels

17. Urine is consider as toxic material as it contains: 1- Nitrogenous wastes 2-Other normal solutes include: ( Sodium, potassium, phosphate, etc……) 3-Abnormally urinary constituents may indicate pathology

18. 1.Kidney Stones: Kidney stones are solid masses of mineral salt. 2.Polyuria (or diuresis): output in excess of 2 L/day Causes– fluid intake, some drugs, diabetes 3.Oliguria: output of less than 500 mL/day 4.Anuria: output of 0-100 mL/day Causes– kidney disease, dehydration, etc. 5.Dialysis: blood filtration procedure done if there is failure of the kidney.