Medical assisting Administrative and clinical procedures (5e) Chapter 31 The urinary system

The learning objectives for this chapter include: Describe the structure, location, and functions of the kidney; explain how nephrons filter blood and form urine; compare the locations, structures, and functions of the ureters, bladder, and urethra; describe the causes, signs and symptoms, and treatments of various diseases and disorders of the urinary system.

CHAPTER 31 The Urinary System 31-2 Learning Outcomes (cont.) 31.1 Describe the structure, location, and functions of the kidney 31.2 Explain how nephrons filter blood and form urine 31-3 Learning Outcomes (cont.) 31.3 Compare the locations, structures, and functions of the ureters, bladder, and urethra 31.4 Describe the causes, signs and symptoms, and treatments of various diseases and disorders of the urinary system 31-4 Introduction Kidneys Kidneys Ureters Ureters Bladder Bladder Urethra Urethra • System functions to remove waste products from the blood • Nephrons filter the blood and form the urine 31-5 The Kidneys • Maintain homeostasis – Remove metabolic waste products – Secrete hormones • Erythropoietin • Renin – Retroperitoneal at level of lumbar vertebrae Kidneys 31-7 The Kidneys (cont.) • Renal sinus – Concave depression on the kidney's surface – Hilum • Renal pelvis – Expansion of the ureter – Divides into calyces Kidney 31-8 The Kidneys (cont.) • Renal cortex – outermost layer • Renal medulla – Middle portion – Divides into renal pyramids • Renal column – between pyramids Kidney 31-10 Nephrons • Renal corpuscle – Glomerulus ~ capillaries – Bowman’s capsule Nephron 31-11 Nephrons • Renal tubules – extend from Bowman’s capsule – Proximal convoluted tubule – Loop of Henle – Distal convoluted tubule Nephron 31-12 Nephrons (cont.) Renal artery Renal vein Afferent arterioles Peritubular Capillaries Glomerulus Efferent arterioles Nephron 31-21 Urine Composition • Mostly water • Urea and uric acid • Trace amounts of amino acids and various ions • Secretion of waste products helps to maintain the acid-base balance 31-22 Apply Your Knowledge Match the following: ANSWER: B Second process in urine formation _ C Substances move from blood _ into renal tubules reabsorption A _ Depends on filtration pressure A Glomerular filtration B Tubular Reabsorption C Tubular Secretion C Third process of urine formation _ A _ First process of urine formation B _ Filtrate flows into the proximal convoluted tubule 31-24 Urinary Bladder • Trigone – triangle on internal floor of bladder • Detrusor muscle – smooth muscle of bladder wall • Micturition – Process of urination – Triggered by stretching of the bladder Bladder 31-26 Urinary Bladder (cont.) • Micturition Impulses to contract urethra  inhibit micturition impulse until ready to urinate Brain stem and cerebral cortex Spinal cord Parasympathetic nerves stimulate detrusor muscle Stretch receptors Bladder distends 31-27 Urethra • Moves urine from the bladder to the outside world • Shorter in females – patient education – Urinate when urge occurs – Drink adequate clear fluids – Wipe front to back – Urinate after intercourse Urethra 31-28 Apply Your Knowledge True or False: ANSWER: T Ureters move urine by peristalsis _ F The detrusor is formed by the openings of the ureters _ and urethra trigone T The process of micturition is triggered when the bladder _ contains about 150 ml urine ureters F The urethra move urine from the kidney to the bladder _ F The urethra is longer in females _ males T Contraction of the detrusor muscle pushes urine from _ the bladder 31-29 Diseases and Disorders of the Urinary System Disease/Disorder Description Acute kidney (renal) failure Sudden loss of kidney function; may be reversible with treatment Chronic kidney (renal) failure Kidneys slowly lose ability to function; not reversible Cystitis Urinary bladder infection; more common in females 31-30 Diseases and Disorders of the Urinary System Disease/Disorder Description Glomerulonephritis Inflammation of the glomeruli of the kidney; one cause of chronic renal failure Incontinence Inability to control urination Polycystic kidney disease Enlargement of kidneys because of the presence of many cysts within them; slow, progressive disease 31-31 Diseases and Disorders of the Urinary System Disease/Disorder Description Pyelonephritis Complicated urinary tract infection; begins with a bladder infection and spreads to both kidneys; can be acute or chronic Renal calculi Kidney stones; can become lodged in ducts within kidneys or ureters 31-32 Apply Your Knowledge Matching: ANSWER: G O B Glomerulonephritis O C Incontinence D D Chronic renal failure J E Renal calculi O F Cystitis B G Acute renal failure ! H Polycystic kidney disease A Complicated urinary tract infection A Pyelonephritis _ C Inability to control urination _ E Kidney stones _ D Slow loss of kidney function _ F Bladder infection _ B Inflammation of the glomeruli _ H Kidney enlargement due to cysts _ G Sudden loss of kidney function _ 31-33 In Summary 31.1 The retroperitoneal kidneys are composed of the outer renal cortex and inner renal medulla Their function is to remove metabolic wastes from the body 31-34 In Summary 31.2 A nephron is a single kidney cell It is composed of a renal corpuscle composed of the glomerulus and the Bowman’s capsule and the three sections of the renal tubule: the proximal convoluted tubule, the loop of Henle, and the distal convoluted tubule The nephrons filter blood and form urine through three processes: glomerular filtration, tubular reabsorption, and tubular secretion 31-35 In Summary (cont.) 31.3 The ureters are long tubes extending from each renal pelvis that bring urine to the bladder for storage The urethra is the muscular tube extending from the bladder that allows urine to be expelled from the body 31-36 In Summary (cont.) 31.4 There are many common diseases and disorders of the urinary system with varied signs, symptoms, and treatments Some of these include acute kidney (renal) failure, chronic kidney (renal) failure, cystitis, glomerulonephritis, incontinence, polycystic kidney disease, pyelonephritis, and renal calculi 31-37 End of Chapter 31 This too shall pass—just like a kidney stone ~H Madson ... Compare the locations, structures, and functions of the ureters, bladder, and urethra 31. 4 Describe the causes, signs and symptoms, and treatments of various diseases and disorders of the urinary system. .. composed of the glomerulus and the Bowman’s capsule and the three sections of the renal tubule: the proximal convoluted tubule, the loop of Henle, and the distal convoluted tubule The nephrons... because of the presence of many cysts within them; slow, progressive disease 31- 31 Diseases and Disorders of the Urinary System Disease/Disorder Description Pyelonephritis Complicated urinary tract