2. Functions and organs The urinary system has the job of creating homeostasis in the body, remove waste products, add or reduce water and electrolytes in the body, and maintain right amount of pH in the body The organs of the urinary system include Kidneys Ureters Urethra Urinary bladder
3. The Kidneys Located in the lumbar region of the back above the waist on either side of the vertebral column. Has a concave(indented area) in the center called the hilum. Renal arteries enter and renal veins leave the kidneythrough the hilum. The working part of the kidney is the nephron. Several visible structures of the kidney are Cortex(outer portion) Medulla(inner area) Renal pyramids(inside the medulla)
4. Kidneys continued Renal papilla(tip of pyramids) Calyx( continues on to the renal pelvis). Nephronsconsist of Renal corpuscle(blood filtering part) Glomerular/Bowmans capsule Afferent arteriole Efferent arteriole Renal tubule(finish urine making process) Proximal convoluted tubule Loop of henle Distal convoluted tubule Collecting tubule
5. The ureters Narrow tubes that measure less than ¼ inch wide and 10 to 12 inches long. They extend from renal pelvis to the bladder. Lined with mucous membranes. Two of them
6. Urinary bladder Elastic muscular sac lying in the base of pelvis behind pubic symphysis. Made of three layers of smooth muscle tissue with rugae (folds) that allow it to stretch. Bladder receives urine directly from ureters, stores it,and excretes it(urination) through the urethra. Usually, adults store 250ml of urine Internal sphincter keeps us from urinating at the wrong time. External sphincter opens when we want to urinate at the right time.
7. urethra Tubular canal which carries flow of urine from bladder to outside of body. External opening is called urinary meatus. Mucous membrane lines this also. 1 ½ inch long in females, 8 inches long in males. For women it functions as outlet for urine For men it serves two purposes Outlet for urine Passageway for semen
8. Kidneys part in homeostasis Adjust chemical conditions in the body. Proper balance of water Electrolytes(sodium, potassium, chloride. bicarbonate). Maintain correct pH Not too acidic in the body. Not too much alkaline in the body.
9. Urine and its production Urine in the last form, to be eliminated is the product of the process. Three stages Filtration- filtering of particles in the renal corpuscle. Reabsorption- filtrate passes through four sections of the tubule. Water and most electrolytes and nutrients are reabsorbed into the peritubular capillaries. They then reenter the moving blood. Secretion- special cells of renal tubules secrete waste substances directly into the renal tubule. Urine is now formed and complete; passing into collecting tubes, renal papilla, calyx, renal pelvis, and into the ureter. Urine- normally straw colored and clear. May contain dissolved substances(electrolytes, toxins) Normal urine is acidic During a 24 hour period normal output will be 1000-2000mL.
10. Some common terms Cystitis- bladder inflammation. Nephrolith-kidney stone. Nephrectomy- removal of a kidney. Uremia- blood condition of urine. Anuria- condition of no urine. Voiding- another term for urination. Catheter- tube inserted into the body to move fluids in or out of the body. Renal colic- pain caused by a kidney stone. Urgency- feeling the need to urinate immediately.
11. Diagnostic procedures Blood urea nitrogen(BUN)- blood test to measure kidney function by level of waste in blood. Creatinine clearance- test of kidney function by collecting a 24 hour urine specimen. Creatinine is a waste product cleared from the bloodstream by the kidneys. Urine culture and sensitivity(C&S)- lab test of urine for bacterial infection. Intravenous pyelogram- injects a contrast medium into a vein and then take an x-ray to see the renal pelvis.
12. Therapeutic and pharmacology Extracorporeal shockwave lithotripsy- use of ultrasound waves to break up stones. Hemodialysis- use of an artificial kidney machine to filter a persons blood of waste products. Renal transplant- surgical placement of a donor kidney Antibiotic- used to treat bacterial infections of urinary tract. Antispasmodic- medication to prevent/ reduce bladder muscle spasms. Diuretic- medication to increase volume of urine output by kidneys. Useful to treat edema, hypertension, and heart failure.
