urinary system quiz Flashcards
4 main organs of the urinary system
kidney,s ureters, bladder, urethra
kidney overall function
filter blood
ureters overall function
carry filtered contents to the bladder
bladder overall function
holds fluid that is going to be excreted
urethra overall function
carries fluid from the bladder to outside the body
shape of kindeys
bean shaped
kidneys are the primary site of
blood filtration
what stuff are filtered out by the kidneys
extra water, electrolytes, metabolic waste like urea
all waste from the kidneys are excreted in..
urine
3 “other jobs” of kidneys
- make hormone EPO
- filter out blood calcium
- produce enzyme renin
EPO
erythropoietin
what happens when the kidneys make erythropoietin
causes erythrocyte hematopoiesis in bone marrow
what will kidneys do if RBC counts are low
produce more erythropoietin to fix it
when will the kidneys filter out more blood calcium
hypercalcemia
what causes the kidneys to filter more blood calcium in hypercalcemia
calcitonin
when will the kidneys filter out less blood calcium
hypocalcemia
what causes the kidneys to filter out less blood calcium in hypocalcemia
PTH
kidneys filtering blood calcium helps to maintain..
homeostasis
the kidneys produce the enzyme renin in response to what
in response to low blood pressure
what does renin initiate
a negative feedback loop that leads to blood pressure increasing
wat is Angiotensinogen
a protein found at low levels in the blood at all times, biologically inactive
what does renin cut
cuts angiotensinogen into angiotensin I
angiotensin I is still
INACTIVE
angiotensin I is cut by
by angiotensin converting enzyme (ACE)
after angiotensin I is cut it becomes
a smaller version, called angiotensin II
what things can angiotensin II do
- serves as a vasoconstrictor
- causes adrenal glands to release aldosterone
- causes hypothalamus to secrete ADH
how does angiotensin II serve as a vasoconstrictor
causing tunica media of blood vessels to contractt
what happens when blood vessel contract
blood pressure goes up
what happens when angiotensin II causes adrenal glands to release the hormone aldosterone
aldosterone orders the kidneys to leave more sodium and potassium ions in the blood
more sodium and potassium ions in the blood cause
more water entering the bloodstream through osmosis…. blood pressure goes up
ADH
anti-diuretic hormone
anti-diuretic causes
the kidneys to add less water to the bladder and conserve more for the body
the kidneys adding less oxygen to the blood means…
more plasma, so blood pressure goes up
how much of the body’s blood flow do the kidneys receive
25%
how much blood per minuet do the kidneys receive
1.1 litres
blood comes towards the kidneys from where
the renal arteries
the renal arteries break into what
into arterioles then capillaries
what are capillaries
the smallest type of blood vessel and small substances can diffuse through their thin walls
why are capillaries in the kidneys interesting
they form glomeruli
what are glomeruli
clusters or tufts of looped vessels
singular of glomeruli
glomerulus
what things can pass through the walls of a cpillary
small particles
what small particles are able to pass through the walls of a capillary
water molecules, dissolved ions, small proteins, and sugars
what things cannot pass through the walls of a capillary (large things)
red blood cells, white blood cells, platelets
what is the functional unit of the kidney
the nephron
how many nephrons do each of the two kidneys contain
1 million nephrons
two main parts of the nephron
the renal corpuscle, the renal tubule
what does the renal corpuscle do
filters things out of the blood
what does the renal tubule do
carries the filtered stuff towards the ureters
after filtered stuff goes to the ureters
goes to the bladder, then the urethra
two parts of renal corpuscles
glomerulus and bowman’s capsule
glomeruli are found where
at the entrance of every nephron
what is surrounding the glomerulus
cup-like structure called Bowman’s capsule
what is filtrate
stuff filtered out of the blood by the glomeruli
what happens to the filtrate in the bowman’s capsule
it gets caught
what happens after filtrate is caught in the Bowman’s capsule
it enters the renal tubule and heads towards the ureters
how much filtrate does the body produce per day
180 liters ( only some becomes urine)
fluid collected into the bowman’s capsules embarks…
down the renal tubule towards the ureter
the renal tubule touches what at many points
touches blood vessels at many points
the renal tubules can transfer
certain particles into or out of the blood at certain regions along it
things that can happen in the tubule:
- reabsorption
- secretion
- excretion
reabsorption in renal tubule
smaller, valuable molecules in filtrate exit the renal tubule and re-enter the blood stream
what valuable things are reabsorbed in the renal tubule
glucose, ions, important proteins, some of the water
how does secretion happen in the renal tubule
the body can take other things from the blood that was not filtered and dump them into the filtrate
what things are secreted in the renal tubules
protons, urea, antibiotics, drugs, creatine
how does excretion happen in the renal tubules
anything still in the renal tubule after reabsorption and secretion leaves the kidney and travels down the urinary tract
are stuff in reabsorption seen in filtrate
no
different things in the renal tubules can
get added or removed in different regions
different regions in the renal tubules can be
manipulated into filtering / secreting more or less based on the presence of hormones (PTH or ADH)
3 regions of the renal tubules from beginning to end
- proximal convoluted tubule
- loop of Henle
- distal convoluted tubule
the loop of Henle can sometimes be broken into
into the descending loop and the ascending loop
what happens to any fluid left in the kidneys after filtration, reabsorption, secretion and excretion
begins to pool in the renal pelvis
what happens to fluid after it pools in the renal pelvis
drips out of the kidneys and the ureters
after the ureters, fluid eventually lands in the
bladder
how much urine can the bladder hold before you have the urge to pee
300mL (can hold quite a bit more)
the urinary bladder hold urine until
the body decides to release it
the bladder is simultaneously controlled by what muscle
smooth and skeletal
the autonomic portion of the bladder regulates
the detrusor muscle
what is the detrusor muscle
a smooth muscle that surrounds the bladder
pinching the detrusor muscle does what
forces urine out
relaxing the detrusor muscle
lets the bladder hold more urine
what causes the detrusor muscle to contract, forcing liquid out
the parasympathetic nervous system
the parasympathetic nervous system causing the detrusor muscle to contract and forcing urine out is
the U in SLUDGE-PM
for the urinary sphincters there are
one internal, one external
what are the urinary sphincters
two skeletal muscles that people can learn to control in bladder
when you learn to control your urinary sphincters you are
potty trained
when elderly people lose control of their urinary sphincters
incontinence
what is the urethra again?
the tube running from the bladder to the outside of the body
urine runs through the urethra in a
one way flow when the bladder’s sphincters are relaxed
how long is the urethra in men
8 inches long
how long is the urethra in women
2 inches long
what often happens in the urinary tract
becomes infected with bacteria
how do bacteria enter the urinary tract
through the end of the urthera
does the urethra often get infected with bacteria
no
where to UTIs most often happen
the bladder
what happens in mot serious cases of UTIs
when bacteria travels to the kidneys
women have nearly ____ the rate of UTIs
15 times
why are women more prone to UTIs
their urethra is shorter, bacteria have less distance to travel to cause infection
