Exam 4 Flashcards
main functions of kidneys
- excretion of waste
- regulate blood volume, electrolyte (ions) composition, and ph of body fluid
- hormone and production of active agents
- other roles (gluconeogenosis)
what is the location of the kidneys?
they are just outside the abdominal cavity and sit on each side of the spine against the posterior wall
why are the kidneys heavily vascularized?
there needs to be capillaries running through the kidneys to allow for the filtration of blood
what is the typical filtration amount for the kidneys in one day?
about 180 L/day
How much of the filtration in the kidneys is reabsorbed back into the body?
about 179 L/day (only 1 L is lost to urine)
what are two parts of the blood that should not be in urine and are a sign of a disorder/illness?
- glucose
- proteins
what health condition will cause glucose to be excreted in urine?
diabetes
what health condition will cause proteins to be excreted in urine?
preeclampsia
what three parts of the blood are checked to ensure the kidneys are functioning properly?
- urea
- uric acid
- creatinine
what part of the blood, produced by muscles, should ALL be excreted in urine (0 reabsorbed)?
creatinine
3 layers of the kidneys
- renal cortex (outermost)
- renal medulla
- renal pelvis (innermost layer)
renal medulla
a set of cone shaped masses of tissue that secrete urine into sac-like tubules
renal pelvis
a funnel shape surrounded by smooth muscle that uses peristalsis to move urine out of the kidney into the ureter and to the bladder
ureters
aids in movement of urine to the bladder, even without aid of gravity
what is the purpose of the ureter having the muscular layer that consists of longitudinal and circular smooth muscles?
it creates peristaltic contractions that aids in the movement to the bladder, even without aid of gravity
what is transitional epithelium (urothelium)?
unique epithelium that is made up of several layers of cells that become flattened when stretched. It lines most of your urinary tract and allows your bladder to expand.
where is transitional epithelium found?
- ureter
- bladder
what does the transitional epithelium look like when the bladder is empty?
resembles columnar epithelia
what does the transitional epithelium look like when the bladder is full?
resembles a squamous appearance
what are the voluntary and involuntary muscles in the bladder?
- voluntary = detrusor muscle
- involuntary = external urethral sphincter
renal artery
brings in oxygenated blood from the heart to the kidney
renal vein
deoxygenated blood leaving the kidney
what is the order in which the renal artery will branch until reaching the capillaries?
- segmental artery
- interlobar artery
- arcuate artery
- interlobular artery
- afferent arteriole
(glomerulus) - efferent arteriole
afferent arterioles branch from interlobular arteries to the _______________ of the nephron
glomerulus
what is the functional unit of the kidney?
nephron
renal papilla
the openings of the the renal pyramid, where urine is transported from the nephrons to the collecting ducts
renal pyramids
where nephrons are
minor and major calyx
a minor calyx surrounds the renal papilla of each pyramid and collects urine from that pyramid. several minor calyxs converge to form the major calyx
ureter
takes urine to the bladder
what is the order in which the renal veins will branch after the capillaries?
- interlobular vein
- arcuate vein
- interlobar vein
- renal vein
glomerulus
fenestrated capillary network
Bowmans corpuscle
the outside shell around the glomerulus
convoluted tubules
names
- proximal tubule
- distal tubule
afferent arteriole
blood that comes in from the arcuate artery and into glomerulus
efferent arteriole
blood that comes out after the glomerulus and moves through the rest of the nephron and into the arcuate vein
renal corpuscle
the outside shell around the glomerulus
podocyte
a modified pericyte that covers the network or capillaries in the glomerulus, they intermesh to create the third layer in which the filtration of blood takes place
juxtaglomerular cells
synthesize, store and secrete the enzyme renin in response to a drop in blood pressure by stimulation from (nor)epinephrine
macula densa
cells specialized within the wall of the distal tubule that sense the salt content and the volume of fluid within the tubule, they will stimulate juxtaglomerular cells to release renin when they detect a drop in sodium concentration in the tubular fluid
2 types of nephrons
- cortical nephron
- juxtamedullary nephron
cortical nephron
glomerulus is located neared to the outer parts of the cortex and have short loops of Henle
juxtamedullary nephron
glomerulus is located near the junction on the cortex and medulla and have loops of Henle that penetrate deep into the medulla
Nephron function
nephrons filter blood and then reabsorb useful materials from the filtrate before eliminating the remainder as urine
3 key stages to nephron function
- ultrafiltration
- selective reabsorption (both tubules)
- osmoregulation (loop of Henle, collecting duct)