Urinary System Flashcards
Urinary System
composed of 2 kidneys, 2 ureters, one bladder, and one urethra
each ureter drains from the kidneys to the urinary bladder wehre wasted is carried from the urethra to exit the body
kidneys
- bean-shaped organ that is about 5 oz. (size of a soup can)
- right kidney is slighly lower due to the liver aboce it
- both are protected by the rib cage btw T-12 & L-3
function: maintain homeostais of the bodys fluid, blood volume and chemical composition, as well as filter waste
is a cleft in the medial convcave surface of the kidneys that lead to the renal sinus
renal hilus
where the ureters, blood vessels and nerves are, which enter the kidney at the hilus
renal sinus
inner protective layer of the kidney that has a tough fibrous outer skin to protect it from injury and infection
renal capsule
is a fatty protective layer that protects the kidney from trauma outside the renal capsule
adipose capsule
a dense fibrous connective tissue that keeps the kidney in place within the abdominal cavity
renal fascia
is a continous outer region with several projections inside the renal capsule
renal cortex
several projections that extend down btw the renal medulla pyramids
cortical columns
extensions of the pelvis that collect urine and drains it into the renal pelvis
calyces
are divided sections that point toward the center of the kidney in the renal medulla
renal pyramids
What is the centermost section of the kidney near the renal hilis that forms a funnel-shaped tube?
renal pelvis
it connects to the ureters when leaving hilus
What transports urine from the kidneys to the bladder to be stored by these thin muscular tubes
Ureters
- where the kidney and nervous system interact here
- its fibers follow the renal arteries to reach the kidney
renal plexus
where are the sphincters located when the ureters enter bladder?
ureterovesical valves
the downward flow of urine through here helps to prevent back flow of urine to the kidneys
is a hollow, muscular, elastic pouch that revives and stores urine exreted by the kidneys before disposal through the urethra
bladder
What’s the different btw male and female bladder
male bladder is located at the base of the rectum and behind the pubic symphysis
female bladder is located below the uterus and in front of the vagina
the max capacity of the bladder is lower than males b/c there are more organs
are where the ureters open into the bladder
ureteral orifices
smooth, triangular center region of the bladder
trigone
is the middle muscular layer of the bladder that contains inner and outer longitudinal layers
detrusor muscle
specialized cells that enable cellular expansion in order to absorb fluid
this makes up the inner mucosal layer of the bladder wall
transitional epithelium
What are the folds in the bladder wall that extend to help internal bladder capacity?
Rugae
what is the release of urine from the bladder through the urethra and urethral orifices
micturition
- is the amount of pressure inside the blood of the capillaries which drives fluid out of them
- varies from person to person depending on BP from their heart and vessels
- it has a direct relationship with BP (when one increases, the other increases)
blood hydrostatic pressure
What is the measurement in which all fluid pressures in glomerular fliltration are recorded?
mmHg (milimeters of mercury)
This depends on the amount of proteins in the blood and opposes hydrostatic pressure by driving fluids back into capillary beds to draw water out of fitrate?
also known as oncotic pressure
colloid osmotic pressure (COP)
What is the mechanical pressure exerted by recoil of the elasticiy inside the glomerular arterioles that also opposes blood HP and drives fluid back into the glomerular capillaries?
capsular hydrostatic pressure
What is the difference in pressure btw ougoing and incoming forces at the glomerulus?
Net filtration pressure (NFP)
what is the flow of blood through the vessels of the kidney?
Renal artery Segmental artery (5) Lobar artery Interlobar artery Arcuate artery Interlobular artery Afferent arteriole Glomerular capillaries Efferent arteriole Peritubular or vasa recta capillaries Interlobular vein Arcuate vein Interlobar vein Renal vein
How much can the bladder hold?
500 ml, and 1000ml if completely necessary
what is the tube from bladder to exterior and has
sphincters to the control exit of urine
the ureters
What has a normal range btw 25 - 32 mmHg
Colloid osmotic pressure (COP)
what is the functional and structural unit of a kidney?
A nephron
How many times does the kidneys filter the blood plasma volume each day?
60 times
also uses about 25% of the body’s resting energy to excrete wastes
How much glomerular filtrate is removed daily?
About 47 gallons containing water, nutrients, and essential ions are removed daily
by the time filtrate enters the collecting ducts, it contains only about 0.5 gallonsof urine
what are the 3 processes essential for filtering the blood?
Filtration, Reabsorbtion and Secretion
What is urochrome?
It is a pigmented blood product that gives the yellow color of urine
What are solutes are found in the urine?
Na+, K+, HCO3-, Urea, Uric acid, creatinine, NH3, etc
What are solutes are NOT found in the urine?
glucose, blood, proteins, RBCs, hemoglobin, WBCs (pus), bile
Why do the kidneys have a rich blood supply?
they continuously cleanse the blood and adjust its composition
What are the two main structures of a nephron?
The renal tubule and the glomerulus
What prevents the passage of blood from exiting the capillaries?
The size of the capillary fenestrations, which also prevents most of the blood proteins from exiting as well
What does a three regions of the inner kidney are shown in a vertical cross section ?
The renal pelvis, renal cortex and medulla.
What adjusts the diameter of the renal arteries thereby regulating renal blood flow. ?
in put from the sympathetic nervous system
What is the amount of blood filtered by the glomerulus over time called?
the glomerular filtration rate
What is the normal GFR rate?
120-125 ml/min or 180L/day due to large surface area of glomerular caillaires
What causes the GFR to increase?
An increase in the arteriral/glomerular blood pressure in the kidneys
What causes the GFR to decrease?
An increase in glomerular osmotic pressure due to dehydration
Why is it important to maintaina constant GFR?
to allow adequate reabsoprtion of water and other needed substances from the filtrate and filtration of wates
What happens if the GFR flow is too slow?
`nearly all the filtrate is reabsorbed, which includes most of the wastes that should be excreted
What happens if the GFR flow is too fast?
Needed substances cannot be adequately reabsorbed
What are the 3 mechanisms that regulate renal blood and GFR?
renal autoregulation, nervous system control, and hormone control
what is the mechanism in which the kidney controls its own rate of blood flow by controlling the diameter of afferent and eferent arterioles?
renal autoregulation
What mechanism occurs in an emmergency to divert blood away from kidnyes to vital organs (brain, heart, skeletal muscles)?
nervous system control
What happens when nervous system control takes over?
It supersedes renal autoregulation, and causes the afferent arterioles to narrow in diameter caused by the sympathetic nerv fibers
What hormone is released by the adrenal medulla in the adrenal glands?
Epinephrine
What does the release of epinephrine do?
It causes a decrease in the renal blood flow and decreases the glomerular filtration rate (GFR)
What would happen if the nervoys system constricted lood flow to the kidneys for a long time?
Damage to the kidneys may occur b/c of the decreased blood supply to the kidney’s cells
what is the hormonal mechanism that controls renal flow and GFR called?
The renin-angiotensin-aldosterone (RAA) system?
what are the 3 layers of the ureter walls
- outer adventitia - fibrous connective tissue
- middle muscular layer: 1 longitudinal and 1 circular
- inner lining - transitional epithelium and is continuous with the kidney’s linings.
When does the RAA system respond?
When the body’s blood pressure drops too low
Is a pre-enzyme that is produced by the liver and freely circulates in the blod
angiotensinogen