Berryhill and cashion Hs1, dho ch 7.12, pg 2016-2017 Urinary system a&P Berryhill and cashion Hs1, dho ch 7.12, pg 2016-2017

Urinary system AKA excretory system Removes wastes & excess water Maintain acid-base balance Helps maintain body’s homeostasis

Urinary system Parts of the urinary system: 2 kidneys 2 ureters 1 bladder 1 urethra

kidneys Bean-shaped organs Found on either side of vertebral column Located in retroperitoneal space Retroperitoneal space=area behind upper part of abd cavity; separated from abd cavity by peritoneal membrane

kidneys Protected by Ribs & fat cushion Held in place by connective tissue Each kidney is enclosed in mass of fatty tissue=adipose capsule Each kidney is covered by a tough, fibrous tissue=renal fascia or fibrous capsule

Where are the kidneys located? retroperitoneal space Test your knowledge Where are the kidneys located? retroperitoneal space Can you think of an example of the urinary system’s ability to maintain homeostasis?

answer A good example is when a person drinks a large amount of water and urinary output increases

kidneys Divided into 2 main sections: cortex & medulla Cortex= outer section contains most of the nephrons (Nephrons aid in production of urine)

kidneys Medulla= inner section Contains most of the collecting tubules (collecting tubules carry urine from nephrons through the kidney)

kidneys Each kidney has a hilum Hilum=notched or indented area the ureter, nerves, blood vessels, & lymph vessels enter & leave the kidney through the hilum

Test your knowledge So, let’s think this through….you have to produce the urine first and then send the urine out of the kidney. In what order does fluid pass through the kidney and its layers on the way to the ureter?

answer Cortex to the medulla to the hilum

kidneys Nephrons=microscopic filtering units of the kidney There are more than 1 million nephrons per kidney

kidneys Each nephron consists of a: Glomerulus Bowman’s capsule Proximal convoluted tubule Distal convoluted tubule Collecting duct (tubule)

kidneys The renal artery carries blood to the kidney Branches of the renal artery pass through the medulla to the cortex This is where blood enters the 1st part of the nephron, the glomerulus glomerulus=cluster of capillaries

This is the start of the process of filtration!!!

kidneys Water, mineral salts, glucose, metabolic products, & other substances are filtered out of the blood as it passes through the glomerulus Rbcs & proteins are not filtered out

kidneys Filtered blood leaves the glomerulus & moves to the renal vein which carries it away from the kidney The substances filtered out by the glomerulus enter the next section of the nephron, Bowman’s capsule

kidneys Bowman’s capsule=C-shaped structure that surrounds the glomerulus It is the start of the convoluted tubule Bowman’s capsule picks up the filtered materials & passes them into the convoluted tubule

kidneys As the filtered material passes through the tubule, substances needed by the body are reabsorbed and returned to the blood capillaries Those substances are most of the water, glucose, vitamins, and mineral salts

Question During the process of filtration in the nephron, most of the water, glucose, and vitamins are: Stored in the bladder Excreted through the ureters Reabsorbed into the blood Concentrated in the urine

c. Reabsorbed into the blood answer c. Reabsorbed into the blood

kidneys excess glucose and mineral salts, some water, and wastes (urea, uric acid, and creatinine) remain in the tubule These excess substances are a concentrated liquid=urine

kidneys Urine enters collecting ducts (tubules) located in the medulla The collecting ducts empty into the renal pelvis (renal basin), Renal pelvis=funnel-shaped structure that is the 1st section of the ureter

Test your knowledge What would you find inside the glomerulus? blood What c-shaped structure in the nephron surrounds the glomerulus? bowman’s capsule

ureters 2 Muscular tubes 10-12 inches long Renal pelvis=funnel-shaped 1st section of ureter One ureter extends from the renal pelvis of each kidney to the bladder

ureters Peristalsis moves urine through ureter from kidney to bladder

bladder Hollow, muscular sac Found behind symphysis pubis Located at midline of pelvic cavity Receives urine from ureters Stores urine until it is voided Void=urinate=micturate

bladder Lined with mucous membrane Mucous membrane Has rugae (folds) Rugae disappear as bladder expands to fill with urine Bladder Walls are made of triple layer of visceral (smooth) muscle

bladder Circular sphincter muscle controls the bladder opening to prevent emptying Receptors in bladder send out a reflex action which opens the muscle Urge to void occurs when bladder has 250mL but it can hold much more

bladder Infants cannot control the reflex action As children grow, they learn to control the reflex

Test your knowledge What are the different terms used to describe “someone peeing”?

Answer To void To urinate To micturate

Test your knowledge In what part of the urinary system does peristalsis occur? ureter if you could see the inside of an empty bladder, what would you see? rugae

urethra Tube that carries urine from bladder to outside of body Urinary meatus=external opening of urethra

urethra Female urethra: 1.5 inches long opens in front of vagina carries only urine

urethra Male urethra: 8 inches long Passes through the prostate gland Exists the penis Carries both urine & semen (not at the same time)

Test your knowledge The urethra in the male serves to body systems, what are they? urinary and reproductive What is the last structure urine passes before leaving the body? urinary meatus

urine Liquid waste product of urinary system Aprox 95% water Contains dissolved waste products: urea, uric acid, creatinine, mineral salts, pigments

urine Excess useful products (like sugar) can also be found in urine When useful products are in urine, it usually indicates disease

urine Kidneys filter about 150 quarts of liquid daily About 1,500-2,000 mL (1.5-2 quarts) of urine are produced daily

question What is considered a normal component of urine? Bacteria Sugar Uric acid Red blood cells

DISease!! Answer Uric acid is considered a normal part of urine Ok, let’s take it one step further….what should you think if useful products are found in urine? DISease!!

Urination terms Terms used to describe conditions that affect urination: polyuria=excessive urination Oliguria=below normal amount of urine Anuria=absence of urination Hematura=blood in urine

Urination terms Pyuria=pus in urine Nocturia=urination at night Dysuria=painful urination Retention=inability to empty bladder Incontinence=involuntary urination

Urination terms Proteinuria=protein in urine Albuminuria=albumin (a blood protein) in urine

Test your knowledge Which urinary term would you apply to this situation? Patrice is not ill but drank a large amount of ice tea. You would expect her to have….? polyuria

Apply your knowledge A construction worker falls and strikes his lower abdomen on a hard object. What might he experience as a result? Which medical term would you apply to this situation? Answer-hematuria