Urinary system Flashcards
What are the 6 functions of the urinary system
- Filtration of blood 2. Production and excretion of urine 3. Regulation of fluid and electrolyte balance 4. Excretion of wastes 5. Regulation of blood composition 6. Regulation of blood pH
What are the 4 main components of the urinary system
- Kidneys 2. Ureters 3. Urinary Bladder 4. Urethra
Kidneys filter ______ and produce _____
blood and produce urine
Ureters transport
urine to the bladder
Urinary bladder stores
urine
Urethra transports
Urine out of the body
The kidney lie in the _______ position
retroperitoneal position
The kidneys are externally covered by a
Fibrous capsule and layers of fat
Miscroscopic functional filtration units of the kidneys
Nephrons
What are the 2 major regions of a nephron
- Renal corpuscle 2. Renal tubule
The renal corpuscle is where
filtration occurs
What 2 structures are in the renal corpuscle
- Glonerulus 2. Bowman’s/ glomerular capsule
The renal tubule consists of what 3 structures
- Proxymal convoluted tubule 2. nephron loop 3. Distal convoluted tubule
Specialized capillaries in the renal corpuscle that filter blood
glomerulus
surrounds the glomerulus and captures filtrate
Bowman’s/glomerular capsule
primary site of reabsorption
proxymal convoluted tubule
what 2 parts of the renal tubule are sites of reabsortion and secretion
- nephron loop 2. Distal convoluted tubule
What are the 2 types of nephrons
- Cortical nephrons 2. Juxtamedullary nephrons
Which type of nephron is shorter
Cortical nephrons
What type of nephron makes up 85% of nephrons
Cortical nephrons
Which type of nephron helps regulate urine concentration
Juxtamedullary nephron
What percentage of cardiac output goes directly to the kidneys
20-25%
Urine formation involves what 3 processes
- Glomerular filtration 2. Tubular reabsorption 3. Tubular secretion
Where does glomerular filtration occur
the glomerular capillaries
What substances should be included in filtrate
water and dissolved solutes
What substances should not be included in filtrate
Formed elements and large plasma proteins
Glomerular capillaries are _____ to allow substances to pass through
fenestrated (porus)
Filtration of urine is driven by
hydrostatic pressure
Kidneys are capable of producing _______ L of filtrate per day
180
Amount of filtrate produced/ minute
glomerular filtration rate
What is the normal GFR range
90-120 mL/min
Lower than average GFR can indicate
kidney disease or kidney failure
How is GFR measured
blood test or creatinine clearance test
What are 3 regulators of GFR
- Renal autoregulation 2. Atrail natriuretic peptide 3. Sympathetic innervation
What hormone increases GFR
Atrial natriuretic peptide
What hormone decreases GFR
sympathetic innervation
Reclamation of substances from filtrate/ tubular fluid
Tubular reabsorption
What regulates the reabsorption of water
ADH and Aldosterone
What 2 hormones regulate the reabsorption of Sodium
- Aldosterone 2. Atrial natriuretic peptide
What hormone increases sodium reabsorption
Aldosterone
What hormone decreases sodium reabsorption
Atrial natriuretic peptide
What regulates potassium reabsorption
Degree of sodium reabsorption
What regulates Calcium reabsorption
PTH and Calcitonin
What regulates hydrogen ion reabsorption
fluctuations in blood pH
If blood pH is too low hydrogen ions are
secreted
If blood pH is too high hydrogen ions are
reabsorbed
Bicarbonate ion reabsorption is regulated by
fluctuations in blood pH
excretion of substances that are not needed by the body
tubular secretion
tubular secretion prevents accumulation of what 3 things
- Metabolic/ nitrogenous wastes 2. Hormones 3. Foreign substances
Kidney stones are also called
Renal calculi
Kidney stones form from buildup of
crystalline minerals in the kidney
What are 3 risk factors to developing kidney stones
- Family history 2. medications 3. dehyrdration
Urine is the product of
filtered and processed blood plasma
urine is _______ percent water
95
urine is ______ percent solutes
5
What is the average volume of urine/ day
1-2 L
the pH of urine is normally
4.5 - 8.0
The urinary bladder is
and expandable muscular container
The bladder can comfortably hold
300-400 mL
In total the bladder can hold
700-800 mL
In males the bladder is _____ to the rectum and _____ to the prostate gland
anterior to rectum and superior to prostate gland
What is the muscularis layer of the bladder
detrusor muscle
The bladder is ______ to the uterus in females
anteroinferior
The urethra is lined with
epithelial tissue
What 2 sphincters restrict the release of urine
- Internal urethral sphincter 2. External urethral sphincter
The female urethra is how long
3-4 cm
The female urethra only passes
urine
The male urethra is how long
18-20 cm
The male urethra passes
urine and semen
The internal sphincter is controlled by what type of muscle
smooth muscle (involuntary control)
The external sphincter is controlled by what type of muscle
skeletal (voluntary control)
Urination is also called
micturition
What are the 2 reflexes associated with urination
- Storage reflex 2. Micturition reflex
With the storage reflex as urine fills the bladder the detrusor _____ and internal urethral sphincter is ________
relaxes and the internal urethral sphincter is contracted
With the micturition reflex when the bladder is filled with 200-300 mL of urine the bladder distends which stimulates the detrusor to _______ and internal urethral sphincter to ______
contract and internal urethral sphincter to relax
Urinary tract infections occur when
bacteria or fungi multiply within the urinary tract
Women are more prone to UTIs due to
shorter urethra and close proximity of urethral orifice to anal orifice
When an infection first develops in the urethra it is called
urethritis
If an infection spreads to the bladder it is called
cystitis
If an infection spreads to the kidney is is called
pyelonephritis
What are 2 symptoms of urinary tract infections
- Frequency of urination 2. Burning with urination
