urinary.pdf

The Structure of the Urinary System The urinary system, also referred to as the urinary tract. Consists of : ✓ Two kidneys ✓ Two ureters ✓ One bladder ✓ Aurethra The adrenal glands, which are part of the endocrine system, are located on the top of the kidneys. The Functions of the Urinary Sys...

The Structure of the Urinary System The urinary system, also referred to as the urinary tract. Consists of : ✓ Two kidneys ✓ Two ureters ✓ One bladder ✓ Aurethra The adrenal glands, which are part of the endocrine system, are located on the top of the kidneys. The Functions of the Urinary System The urinary system performs many functions that are important in maintaining homeostasis. Homeostasis Is the process through which the body maintains a constant internal environment (home/o means constant, and -stasis means control). The functions include: ✓Maintaining the proper balance of water, salts, and acids in the body by filtering the blood as it flows through the kidneys. ✓Constantly filtering the blood to remove urea, creatinine, uric acid, and other waste materials from the bloodstream. Urea is the major waste product of protein metabolism. Creatinine is a waste product of muscle metabolism. ✓Converting these waste products and excess fluids into urine in the kidneys and excrete them from the body via the urinary bladder. The Kidneys The kidneys constantly filter the blood to remove waste products and excess water. These are excreted as urine, which is 95% water and 5% urea and other body wastes. The kidneys also help the body maintain the proper level of fluid, produce hormones that control blood pressure and make red blood cells, and activate vitamin D to maintain healthy bones.  The term renal means pertaining to the kidneys (ren means kidney or kidneys, and -al means pertaining to). The renal cortex is the outer region of the kidney. This layer of tissue contains more than one million microscopic units called nephrons. The term cortex means the outer portion of an organ. The medulla is the inner region of the kidney, and it contains most of the urine-collecting tubules. A tubule is a small tube. Nephrons The nephrons are the microscopic functional units of each kidney. Urine is produced through the processes of filtration, reabsorption, and secretion. The Process ✓Each nephron contains a glomerulus, which is a cluster of capillaries ✓ Blood enters the kidney through the renal artery and flows into the nephrons. ✓After passing through the filtration system of the glomerulus, the filtered blood containing protein and blood cells leaves the kidney and returns to the bloodstream through the renal vein. ✓The remaining filtrate flows into the renal tubules, where elements, including some water, sugar, and salts, are returned to the bloodstream via a nearby capillary. ✓ Remaining waste products are continuously converted into urine, which is transported to the renal pelvis and collected in preparation for entry into the ureters. ✓If waste products are not efficiently removed from the bloodstream, the body cannot maintain homeostasis, with a stable balance of salts and other substances. The Renal Pelvis The renal pelvis is the funnel-shaped area inside each kidney that is surrounded by the renal cortex and medulla. This is where the newly formed urine from the nephrons collects before it flows into the ureters. The Ureters The ureters are two narrow tubes. Transport urine from the kidney to the bladder. Peristalsis Is a series of wave-like contractions, moves urine down each ureter to the bladder. Urine drains from the ureters into the bladder through the ureteral orifices in the wall of the urinary bladder. The Urinary Bladder The urinary bladder is an oval, hollow muscular organ that is a reservoir for urine before it is excreted from the body. The bladder is located in the anterior portion of the pelvic cavity behind the pubic symphysis. the bladder is lined with folds allow it to expand when full and contract when empty. The Urethra The urethra is the tube extending from the bladder to the exterior of the body. Caution: the spellings of ureter and urethra are very similar! You may find it helpful to remember that the ureter comes first, both anatomically and alphabetically. Vocabulary/Terms Related to the Digestive System.. Urination Also known as voiding or micturition, is the normal process of excreting urine. Aurologist Is a physician who specializes in diagnosing and treating diseases and disorders of the urinary system of females and the genitourinary system of males (ur means urine, and -ologist means specialist). Nephropathy The term nephropathy means any disease of the kidney (nephr/o means kidney, and -pathy means disease). Anuria is the absence of urine formation by the kidneys (an- means without, and -uria means urine). Diuresis Is the increased output of urine (diur means increasing the output of urine, and -esis means an abnormal condition). Dysuria Is difficult, or painful urination (dys- means painful, and -uria means urination). Enuresis Is the involuntary discharge of urine (en- means into, and - uresis means urination). Nocturia Is frequent and excessive urination during the night (noct means night, and -uria means urination). Urinary retention Is the inability to completely empty the bladder when attempting to urinate, this condition is also more common in men and is frequently associated with an enlarged prostate gland. Incontinence Is the inability to control the excretion of urine, feces, or both. Renal failure Also known as kidney failure, is the inability of one or both of the kidneys to perform their functions. Uremia Also known as uremic poisoning, is a toxic condition resulting from renal failure in which kidney function is compromised and urea and other waste products normally secreted in the urine are retained in the blood Acute renal failure (ARF) Has sudden onset and is characterized by uremia, it can be fatal if not reversed promptly. Chronic kidney disease (CKD) Also known as chronic renal disease, or kidney failure, is the progressive loss of renal function over months or years. End-stage renal disease (ESRD) is the final stage of chronic kidney disease, and this condition is fatal unless the functions of the failed kidneys are successfully replaced by dialysis, or with a successful kidney transplant. Edema Is excessive fluid accumulation in body tissues that can be symptomatic of nephrotic syndrome and other kidney diseases, this swelling can be in the area around the eyes, the abdomen, or the legs and feet. Hyperproteinuria Is the presence of abnormally high concentrations of protein in the urine (hyper- means excessive, protein means protein, and -uria means urine). Hypoproteinemia Is the presence of abnormally low concentrations of protein in the blood (hypo- means deficient or decreased, protein means protein, and -emia means blood condition). Nephritis Is an inflammation of the kidney or kidneys (nephr means kidney, and -itis means inflammation). Nephroptosis Also known as a floating kidney, is the prolapse, or dropping down, of a kidney into the pelvic area when the patient stands, (nephr/o means kidney, and -ptosis means droop or sag). Anephrostomy Is the placement of a catheter to maintain an opening from the pelvis of one or both kidneys to the exterior of the body (nephr means kidney, and -ostomy means creating an opening). Renal transplantation Commonly known as a kidney transplant, is the grafting of a donor kidney, from either a living or nonliving donor, into the body to replace the recipient’s failed kidneys. Acystectomy is the surgical removal of all or part of the urinary bladder. Aureterectomy Is the surgical removal of a ureter (ureter means ureter, and -ectomy means surgical removal). Urinalysis Is the examination of urine to determine the presence of abnormal elements (urin means urine, and -analysis means a study of the parts). Urinary catheterization Is the insertion of a tube into the bladder to procure a sterile specimen for diagnostic purposes. Dialysis Is a procedure to remove waste products, such as urea, creatinine, as well as excess water from the blood of a patient whose kidneys no longer function (dia- means complete or through, and -lysis means separation). Hemodialysis Is the process by which waste products are filtered directly from the patient’s blood (hem/o means blood, dia means complete or through, and -lysis means separation)