Uri S Flashcards
Function of Urinary System
Eliminate (3)
- Nitrogenous wastes
- Toxins
- Drugs
- Regulate aspects of homeostasis (6)
- Water balance
- Electrolytes
- Acid-base balance in the blood
- Blood pressure
- Red blood cell production
- Activation of vitamin D
Organs of the Urinary System (4)
- Kidneys
- Ureters
- Urinary bladder
- Urethra
Kidneys
-location
-level
- Against the dorsal body wall
- At the level of T12 to L3
What kidney slightly lower
right kidney
Kidney is attached to (3) at ____
ureters, renal blood vessels, and nerves
renal hilus
Atop each kidney is an
adrenal gland
Coverings of the Kidneys (2)
- Renal capsule
- Adipose capsule
surround the kidney
adipose capsule
Surrounds each kidney
renal capsule
Provides protection to the kidney
Adipose capsule
Helps keep the kidney in its correct location
Adipose capsule
Regions of the Kidney
- Renal cortex - outer region
- Renal medulla inside the cortex
- Renal pelvis - inner collecting tube
- Renal cortex -
- Renal medulla-
- Renal pelvis -
- Renal cortex - outer region
- Renal medulla inside the cortex
- Renal pelvis - inner collecting tube
Kidney Structures
- Medullary pyramids -
- Renal columns -
- Calyces
triangular regions of tissue in the medulla
- Medullary pyramids -
- extensions of cortex-like material inward
Renal columns
- cup-shaped structures that funnel urine
towards the renal pelvis
Calyces
The structural and functional units of the kidneys
Nephrons
Responsible for forming urine
Nephrons
- Main structures of the nephrons (2)
- Glomerulus
- Renal tubule
A specialized capillary bed
Glomerulus
Glomerulu is attached to___ on both__ (maintain high pressure)
arterioles
side
Glomerulus is attached on both side of arterioles (2)
- Large afferent arteriole
- Narrow efferent arteriole
Capillaries are covered with ___from the
renal tubule
podocytes
The glomerulus sits within a ___(the first part of the renal tubule)
glomerular capsule
the first part of the renal tubule
glomerular capsule
Glomerular (Bowman’s)capsule
renal tube
Part so renal tubule (4)
Glomerular (Bowman’s)capsule
Proximal convoluted tubule
Loop of Henle
Distal convoluted tubule
Types of Nephrons (2)
- Cortical nephrons
- Juxtamedullary nephrons
- Located entirely in the cortex
- Includes most nephrons
Cortical nephrons
Found at the boundary of the cortex and
medulla
Juxtamedullary nephrons
location
* Cortical nephrons
* Juxtamedullary nephrons
- Cortical nephrons- cortex
- Juxtamedullary nephrons- boundary of the cortex and medulla
Peritubular Capillaries arise from
efferent arteriole of the glomerulus
Normal, low pressure capillaries
Peritubular Capillaries
Peritubular Capillaries is attached to a
venule
Cling close to the renal tubule
Peritubular Capillaries
Reabsorb (reclaim) some substances from
collecting tubes
Peritubular Capillaries
Urine Formation Processes (3)
- Filtration
- Reabsorption
- Secretion
Nonselective passive process
Filtration
Blood cells cannot pass out to the capillaries
Filtration
collected in the glomerular capsule and leaves via the renal tubule
Filtrate
The peritubular capillaries reabsorb several
materials (4)
- Some water
- Glucose
- Amino acids
- lons
- Some reabsorption is ___, most is __
passive
active
Most reabsorption occurs in the
proximal convoluted tubule
Materials Not Reabsorbed (2)
- Nitrogenous waste products
* Urea
* Uric acid
* Creatinine - Excess water
Reabsorption in Reverse
Secretion
Some materials move from the peritubular
capillaries into the renal tubules
Secretion
Some materials move from the peritubular
capillaries into the renal tubules (2)
- Hydrogen and potassium ions
- Creatinine
Materials left in the renal tubule move toward the ureter
Secretion
Characteristics of Urine Used for Medical
Diagnosis
- Color _____
- Sterile
- Slightly ____
- Normal pH of _____
- Specific gravity of _____
- Colored somewhat yellow due to the pigment urochrome (from the destruction of hemoglobin) and solutes
- Sterile
- Slightly aromatic
- Normal pH of around 6
- Specific gravity of 1.001 to 1.035
yellow due to the pigment ___(from the destruction of hemoglobin) and solutes
urochrome
pigment from the destruction of hemoglobin
urochrome
Slender tubes attaching the kidney to the
bladder
ureter
Continuous with the renal pelvis
ureter
ureter enter the ___ of the bladder
posterior aspect
ureter runs behind the
peritoneum
aids gravity in urine transport
Peristalsis
Smooth, collapsible, muscular sac
urinary bladder
Temporarily stares urine
urinary bladder
Trigone has how many openings?
-where are they located
three openings
- Two from the ureters
- One to the urethrea
Urinary Bladder Wall is composed of
-how many layers
three layers of smooth muscle (detrusor muscle)
- Mucosa made of transitional
epithelium
Walls of the urinary bladder are thick and folded in an
empty bladder
Urethra Gender Differences
* Length
* Location
* Function
- Length
- Females - 3-4 cm (1 inch)
- Males - 20 cm (8 inches)
- Location
- Females - along wall of the vagina
- Males - through the prostate and penis
- Function
- Females - only carries urine
- Males - carries urine and is a
passageway for sperm cells
Both sphincter muscles must open to allow
Micturition (Voiding)
Micturition (Voiding)
- The _____is relaxed after stretching of the bladder
- Activation is from an impulse sent to the
___ and then back via the - The ____ must be voluntarily __
internal urethral sphincter
spinal cord, pelvic splanchnic nerves
external urethral sphincter , relaxed
Normal amount of water in the human
body
* Young adult females -
* Young adult males -
* Babies
* Old age -
- Young adult females - 50%
- Young adult males - 60%
- Babies - 75%
- Old age - 45%
necessary for many body functions and
levels must be maintained
Water
Distribution of Body Fluid (2)
- Intracellular fluid (inside cells)
- Extracellular fluid (outside cells)
Extracellular fluid (outside cells)
example (2)
- Interstitial fluid
- Blood plasma
The Link Between Water and Salt (3)
-electrolyte
-blood
-cells
- Changes in electrolyte balance causes water to move from one compartment to another
- Alters blood volume and blood pressure
- Can impair the activity of cells
Water intake must equal water
output
- Sources for water intake (2)
- Ingested foods and fluids
- Water produced from metabolic processes
- Sources for water output (4)
- Vaporization out of the lungs
- Lost in perspiration
- Leaves the body in the feces
- Urine production
produced if water intake is excessive
Dilute urine
produced if large amounts of water are lost
Less urine (concentrated)
Proper concentrations of various ___ must be present
electrolytes
Regulation of Water and Electrolyte
Reabsorption (2)
- Regulation is primarily by hormones
- Cells in the kidneys and hypothalamus are active monitors
prevents excessive water loss in urine
Antidiuretic hormone (ADH)
regulates sodium ion content of extracellular fluid
Aldosterone
Aldosterone is triggered by what mechanism
rennin angiotensin mechanism
active monitors (2)
Cells in the kidneys and hypothalamus
Blood pH must remain between ____ and __
maintain homeostasis
7.35 and 7.45
Alkalosis - pH
Acidosis - pH
Alkalosis - pH above 7.45
* Acidosis - pH below 7.35
Most ions originate as byproducts of
cellular metabolism
Most acid-base balance is maintained by the
kidneys
- Other acid-base controlling systems (2)
- Blood buffers
- Respiration
Molecules react to prevent dramatic changes in hydrogen ion (H+) concentrations
Blood Buffers
Buffer
* Bind to H+ when pH
* Release H+ when pH
- Bind to H+ when pH drops
- Release H+ when pH rises
Three major chemical buffer systems
- Bicarbonate buffer system
- Phosphate buffer system
- Protein buffer system
- Mixture of carbonic acid (H,CO3) and sodium bicarbonate (NaHCO,)
The Bicarbonate Buffer System
react with strong acids
to change them to weak acids
Bicarbonate ions (HCO,-)
dissociates in the presence of a
strong base to form a weak base and water
Carbonic acid
Carbon dioxide in the blood is converted to ____ and transported in the __
bicarbonate ion
plasma
Increases in hydrogen ion concentration
produces more
carbonic acid
Excess __ can be blown off with the release of carbon dioxide from the lungs
hydrogen ion
Respiratory rate can rise and fall depending on changing
blood pH
Renal Mechanisms of Acid-Base Balance (3
- Excrete bicarbonate ions if needed
- Conserve or generate new bicarbonate ions if needed
- Urine pH varies from 4.5 to 8.0
Urine pH varies from __ to __
4.5 to 8.0
Developmental Aspects of the Urinary System
-third month
-urinary system of newborn (2)
-18 months
-old age
- Functional kidneys are developed by the third month
- Urinary system of a newborn
- Bladder is small
- Urine cannot be concentrated
- Control of the voluntary urethral sphincter does not start until age 18 months
- Urinary infections are the only common
problems before old age
The bladder shrinks with
aging
Urinary retention is common in
males
