Name _________________________
Functions of the Urinary System
Urinary System Notes
 _______________________________________________
 Nitrogenous wastes
 Toxins
 Drugs
 _______________________________________________
 _______________ balance
 Electrolytes
 _______________ balance in the blood
 _______________________
 ___________________________ production
 Activation of _______________________
Organs of the Urinary System




_______________
_______________
_______________
_______________
Location of the Kidneys
 Against the dorsal body
wall in a
___________________
position (behind the
parietal peritoneum)
 At the level of the T12 to
L3 vertebrae
 The right kidney is
slightly lower than the
left (due to position of
the liver)
Coverings of the Kidney
 _________________________
 Surrounds each kidney
 _________________________
 Surrounds the kidney and cushions against blows
 _________________________
 Outermost capsule that helps hold the kidney in place against the muscles of the trunk wall
Regions of the Kidney
 Renal _______________—outer region
 Renal _______________—inside the cortex
 Renal _______________—inner collecting tube
Kidney Structures
 ______________________________—triangular regions of tissue in the medulla
 _______________—extensions of cortex-like material inward that separate the pyramids
 _______________—cup-shaped structures that funnel urine towards the renal pelvis
Blood Supply
 _______________ of the total blood supply of the body passes through the kidneys _____________
 Renal artery provides each kidney with arterial blood supply
Nephron Anatomy & Physiology
 The nephron is the ____________________________________________________ of the kidneys
 Have about _______________ per kidney
 ________________________________________________
 Main structures of the nephrons
 _______________: Knot of capillaries; sits within a capsule called Bowman’s capsule
 _______________: extends from Bowman’s capsule and ends at the collecting duct
Collecting Duct
 ______________________________ from many nephrons
 Run through the medullary pyramids
 Deliver urine into the calyces and renal pelvis
Urine Formation
 Glomerular filtration – step 1
 Tubular reabsorption – step 2
 Tubular secretion – step 3
Glomerular Filtration
 Nonselective passive process
 ___________________________________________________ are forced through capillary walls
 __________________________________________________________________ through the
filtration membrane
 Filtrate is collected in ______________________________ and leaves via the renal tubule
Tubular Reabsorption
 The peritubular capillaries reabsorb useful substances
 _______________
 _______________
 _______________
 _______________
 Some reabsorption is passive, most is active (needs energy)
 Most reabsorption occurs in the proximal convoluted tubule
 What materials are not reabsorbed?
 Nitrogenous waste products
 _______________—protein breakdown
 _______________—nucleic acid breakdown
 _______________—associated with creatine metabolism in muscles
Tubular Secretion: Reabsorption in Reverse
 Process is important for getting rid of substances not already in the filtrate
 Materials left in the renal tubule ____________________________________________________
Regulation of Water and Electrolyte Balance
 Regulation occurs primarily by hormones
 __________________________ (ADH)
 ___________________________________________________________________
 Causes the kidney’s collecting ducts to reabsorb more water
 Diabetes insipidus
 Occurs when ADH is not released
 Leads to huge outputs of dilute urine
Characteristics of Urine
 In 24 hours, about __________________________ of urine are produced
 Urine and filtrate are different
 Filtrate contains everything that blood plasma does (except proteins)
 Urine is what remains after the filtrate has lost most of its water, nutrients, and necessary ions
through reabsorption
 Urine contains
_________________________________________________________________________
 Yellow color due to the pigment _________________ (from the destruction of hemoglobin) and
solutes
 Dilute urine is a __________________________
 ____________________
 Slightly aromatic
 Normal pH of around ______
Solutes Normally Found in Urine
Solutes NOT Normally Found in Urine
1.
1.
2.
2.
3.
4.
3.
5.
4.
6.
Abnormal Urine Constituents
Substance
Name of
Condition
Glucose
Glucosuria
Proteins
Proteinuria
Pus (WBCs and
bacteria)
Pyuria
RBCs
Hematuria
Hemoglobin
Hemoglobinuria
Bile pigments
Bilirubinuria
Possible Causes
Ureters
 _______________________________________________________________________________
 Continuous with the renal pelvis
 Enter the posterior aspect of the bladder
 Runs behind the peritoneum
 _____________________ aids gravity in urine transport
Urinary Bladder
 Smooth, collapsible, muscular sac
 __________________________
 Trigone—triangular region of the bladder base
 Three openings
 Two from the ureters
 One to the urethra
 In males, the prostate gland surrounds the neck of the bladder
Urinary Bladder Wall




___________ of smooth muscle collectively called the detrusor muscle
Mucosa made of transitional epithelium
Walls are thick and folded in an empty bladder
Bladder __________________________ without increasing internal pressure
Urinary Bladder Capacity
 A moderately full bladder is about 5 inches long and holds about __________________________
 Capable of holding __________________________ of urine
Urethra
 Thin-walled tube that __________________________ from the bladder to the outside of the body
by peristalsis
 Release of urine is controlled by two sphincters
 ____________________________________________________
 Involuntary and made of smooth muscle
 ____________________________________________________
 Voluntary and made of skeletal muscle
Urethra Gender Differences
 Length
 Females is 3 to 4 cm (___________)
 Males is 20 cm (___________)
 Location
 Females—anterior to the vaginal opening
 Males—travels through the prostate and penis
 Prostatic urethra
 Membranous urethra
 Spongy urethra
 Function
 Females—__________________________
 Males—carries _____________________ is a passageway for __________ cells and semen
Urine Elimination
 After urine __________________________, the ureters (starting with the renal pelvis) carry the
urine away to the bladder
 Bladder is an expandable structure that stores urine before it is eliminated from the body.
 Transitional epithelial cells change shape to allow for expansion and contraction.
 __________________ = urination; as the bladder fills this reflex occurs though it is also under
voluntary control
 ____________ = tube carries urine to the outside of the body
 _________________________ - attach to bladder and sphincter, control urination
Disorders of the Urinary System
 Many urinary problems can be solved by __________________________
 So how much fluid does the average, healthy adult living in a temperate climate need? The Institute of
Medicine determined that an adequate intake (AI) for:
 Men is roughly 3 liters (~ __________) of total beverages a day
 Women is 2.2 liters (~ ___________) of total beverages a day
Disorders:




__________________________
__________________________ (aka bladder infection)
__________________________ (aka UTI)
__________________________ (aka incontinence)
When Kidneys Fail…
 Dialysis may be used to clean the __________ (hemodialysis)
 __________________________
 Patients will eventually need a new kidney
Kidney Transplants
 Domino Kidney Transplants or __________________________ - when you aren't a match for a
family member, you can participate in a kidney exchange