Unit 4 Review Flashcards
What are the 3 primary functions of the urinary system?
1) maintaining blood volume and blood pressure
2) maintaining blood pH
3) control plasma concentration
Can you follow a drop of fluid on its way from the blood, to filtrate, to tubular fluid, to urine, to toilet?
capillaries –> glomerulus to become filtrate –> proximal convoluted tubule to become tubular fluid –> nephron loop/loop of henle –> distal convoluted tubes –> collecting system –> nephron –> renal papilla –> minor calyx –> major calyx –> renal pelvis –> ureter –> bladder –> urethra –> toilet
What is the proper term for urination?
micturition
What does it mean that the kidneys are retroperitoneal?
behind the peritoneal membrane
attached to posterior abdominal wall
Know the key parts of the kidney from a sectional anatomy
standpoint.
renal pyramid
a minor calyx
major calyx
renal pevis
ureter
renal corpuscle
glomerulus and glomerular capsule
filtration (small things) is the key function
PCT
proximal convoluted tubules
reabsorption –> 70% of the water almost 100% of the small good things
nephron loop
water reabsorb further, 20% absorbed here
DCT
distal convoluted tubules
secretion is key function
drugs & toxins
collecting system
determines final concentration and volume of your urine
urine should be pale yellow
There are 2 types of nephrons. Which is more numerous? Which is better at concentrating urine?
85% of nephrons are cortical nephrons the better ones are juxtamedullary nephrons
How much filtrate is produced each day? How much fluid enters the collecting system?
48-50 gal of filtrate is produced at the glomerulus
less than 27 liters enters the collecting system
What kind of cells create the filtration slits of the renal corpuscle? What are their false feet called? What kind of capillary beds would be found here?
podocytes (feet cells)
false feet are called pedicles
fenestrated capillaries would be here (large openings)
What is the biggest weakness of the filtration slit/membrane?
filters out small good things, if we didn’t reabsorb we would die
Urea and creatinine are the 2 key metabolic waste products that the kidney must deal with. Where do they come from?
urea is from breakdown of amino acids (21-23 g a day)
creatinine comes from creatinine phosphate
uric acid is the 3RD KEY METABOLIC WASTE PRODUCT (500 mg a day) too much can lead to GOUT
What is the renal threshold/transport maximum?
transport maximum is how many receptors do we have and how fast are they, determines renal threshold, if glucose is in urine, patients BP has to be at least 180 or higher
What is glomerular filtration rate? What does it tell you?
GFR is how much you filter thru kidneys per minute (123 millimeters a minute)
kidneys functioning at 100% should be able to filter 48-50 gal of filtrate
Why is a small drop in blood pressure at the kidneys disastrous?
they’re powered by hydrostatic pressure
20% drop in renal BP would kill the kidneys
What percent of the filtrate that is produced a day reabsorbed as a result of obligatory water reabsorption?
85%
What role does ADH play in concentrating urine?
without it you would have diabetes
you would produce 27 Liters a day without it
What is a diuretic?
anything that increases the loss of water
ex alcohol
What anatomical feature of the ureters prevents the
backflow of urine?
they have a funnel shape, the openings are slits all designed to keep urine from flowing back
How many layers of smooth muscle are in the urinary bladder? What is this muscular layer called?
3 layers
detrusor is the muscular layer