Urinary System Pt 2 Flashcards
This is where the majority (-70%) of the glomerular filtrate is
reabsorbed.
–The ______ is the first segment of the renal
tubule. It begins at the urinary pole of the glomerulus.
proximal convoluted tubule
The convoluted portion of the tubule leads into a straight segment
that descends into the medulla within a medullary ray and becomes
________
the loop of Henle.
(loop on henle) empties into the _____ and Continuous with PCT in cortex
distal convoluted tubule (DCT)
The loop of Henle forms a _____ that dips down into the
medulla.
hair-pin structure
The Loop of Henle contains four segments:
the pars recta (the straight/thick descending limb
of proximal tubule), the thin descending limb, the thin ascending limb, and
the thick ascending limb.
Thick & thin denote the ____ in both the
descending and ascending limbs (loop of henle)
epithelial change (cuboidal to squamous)
The loop of Henle serves to create high osmotic pressure in the renal
medulla via the ____
counter-current multiplier system
The loop of Henle serves to create ______ in the renal
medulla via the counter-current multiplier system
high osmotic pressure
The loop of Henle serves to create high osmotic pressure in the renal
medulla via the counter-current multiplier system. Such high osmotic
pressure is important for the reabsorption of water in the later segments of
the renal tubule, helps create ___
hypertonic urine (excretion of excess solutes).
Loop of Henle surrounded by
peritubular capillary
network, ____
vasa recta
Functions to generate high osmotic
pressure in ECF of renal medulla
via Na-K pumps in thick ascending
limb of loop of Henle
Countercurrent multiplier
Countercurrent multiplier – Functions to generate high osmotic
pressure in ECF of renal medulla
via ____ in thick ascending
limb of loop of Henle
Na-K pumps
Higher extracellular [Na] in
medulla combined with water
resorption by proximal convoluted
tubule in cortex ➔ ____
cortico-
medullary interstitial gradient
Produces counter current
(exchange) multiplier system of
urine concentration—results in
production of ___
hypertonic urine
(Distal convoluted tubule) Continuation of thick ascending
limb of Loop of Henle; present
within cortex
* Simple cuboidal epithelium
with short apical microvilli, but
lacks ___
distinct brush border
Responsible for active
resorption of Na & Cl, coupled
with secretion of H & K ions
(Distal convoluted tubule)
(Distal convoluted tubule) Controlled by 2 cell types:
* ____—resorb Na &
water, secrete K
* ____ – mediate
H+ and HCO3 − secretion,
and Cl− and K+ reabsorption.
Important Regulators of Acid-
Base Balance
principal cells & intercalated cells
—resorb Na &
water, secrete K
principal cells
mediate
H+ and HCO3 − secretion,
and Cl− and K+ reabsorption.
Important Regulators of Acid-
Base Balance
intercalated cells
(Distal convoluted tubule) Controlled by ____
aldosterone
(adrenal mineralocorticoid)
Combined baroreceptor (pressure) & chemoreceptor ([ion])
* Specialized areas of afferent arteriole & distal convoluted tubule
juxtaglomerular apparatus (JGA)
juxtaglomerular apparatus (JGA): Used to regulate systemic blood pressure via ______
renin-angiotensin-aldosterone system
(RAAS)
Three main components of JGA:
Macula densa, Juxtaglomerular cells, Extraglomerular mesangial cells
thickened region on one side of distal convoluted tubule
Contains densely packed cuboidal to columnar epithelial cells
Chemoreceptor sensitive to changes in [Na] in filtrate.
Decrease in systemic BP ➔ decrease in filtrate ➔ decrease [Na]
Macula densa
