Can you hold it long enough for me to get through this lecture? Urinary System Can you hold it long enough for me to get through this lecture?
QUICK REVIEW OF ELIMINATION Lungs eliminate CO2 Sweat glands eliminate excess heat, salt Digestive tract- indigestible solids, bacteria Urinary tract is the main system of elimination
A little vocab Uria or Ur- urine Cyst- bladder Nephr or Ren- kidney Dys- painful
Anuria Cystitis Dysuria Hematuria Hydronephrosis Renal Without urine Inflammation of the bladder Dysuria Painful urination Hematuria Blood I urine Hydronephrosis > water in kidney Renal Pertaining to kidney
The Urinary Tract Urinary tract consists of 2 kidneys, 2 ureters, one bladder and one urethra. Kidney location: Retroperitoneal Dorsal wall of abdominal cavity 12th thoracic and 3rd lumbar vertebrae Urethra 1.5 inches in women, 8 inches in men
Outer layer- Cortex Inner layer- Medulla Calyx- collects urine as it is formed, join together to form the ureter
Kidneys filter blood- 2, 000 L/day (500 gal) remove waste products and reabsorb water, other valuable substances. 1.5 L of urine/day Metabolism produces toxic substances- esp nitrogen containing waste as a by-product of protein breakdown We eliminate nitrogen as urea- water soluble
The main functional unit of the kidney is called the NEPHRON. 1 million per kidney Most of nephron located in renal cortex Loop of Henle is located in the renal medulla
Capillaries in glomerulus filter blood- Bowman’ capsule collects ultra filtrate Through passive and active diffusion, 95% of water is reabsorbed, along with K, Na, Ca Other things are actively excreted, like drugs. Excretion is controlled by hormones such as ADH from hypothalamus
Urine is made in 4 steps Filtration Reabsorption Secretion Excretion A urinalysis is the most common non-invasive medical test ordered
Diseases of the Kidney Acute Kidney failure- sudden loss of function Causes: nephritis, shock, injury, heart failure or poisoning Symptoms: anuria or oliguria. Uremia, nausea, coma, death Chronic Kidney failure- gradual loss of function due to hypertension (high blood pressure) or endocrine disease Cystitis- inflammation of the urinary bladder
Dialysis, Kidney transplant Hemodialysis- serves as an “artificial kidney” 2-3x/week for 2-4 hours Peritoneal dialysis- uses patient’s own peritoneal lining to filter blood Kidney transplant- need suitable donor. Only need one, but must take anti-rejection drugs for the life of the patient