Term
What does urine production regulate |
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Definition
- plasma ion concentrations
- Na+, K+, Ca2+, Mg2+, C1-, HCO3, HPO4-
- Blood Ph
- Plasma volume
- Plasma osmolarity
- Removes wastes and foreign substances
- Retains useful molecules
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Term
How does urine production regulate blood Ph |
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Definition
By regulating the concentration of bicarbonate and hydrogen ions in the plasma, the kidneys partner with the lungs to regulate the pH of the blood |
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Term
How does urine production regulate plasma osmolarity |
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Definition
by regulating the total solute concentraiton of plasma |
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Term
What are the type of wastes found in urine |
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Definition
- metabolic wastes
- urea
- creatinine
- ammonia
- uric acid
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Term
The kidneys secrete Erythropoietin, which stimulates _________ to produce ________ |
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Definition
- bone marrow
- red blood cell production
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Term
Where does urine collect in the kidney |
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Definition
in calyces and the renal pelvis |
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Term
How much blood flows through the kidneys |
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Definition
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Term
Where does the blood return to after it has been processed by the kidneys |
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Definition
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Term
What is the function of nephrons |
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Definition
functional units of the kidnyes, they do the work of filtering the blood and forming the urine |
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Term
How many nephrons are there in two kidneys |
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Definition
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Term
Where is the capsular space found in the kidney |
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Definition
inside the renal corpuscle, on the nephron side of the glomerular epithelium |
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Term
The capsular space funnels into |
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Definition
the proximal convolute tubule (PCT) |
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Term
The distal convoluted tubule drains into a |
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Definition
collecting duct which drains into the renal pelvis |
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Term
Before the blood is filtered, it enters the ______ via an ________ ___________ |
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Definition
glomerular capillaries via an afferent arteriole |
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Term
An efferent arteriole exits the glomerular capillary bed and forms the |
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Definition
peritubular capillary bed, or else a vasa recta, which surrounds the tubules of the nephron or the nephron loop |
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Term
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Definition
blood pressure forces fluid across the filtration membrane, into the capsular space |
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Term
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Definition
most water and some solutes are removed from the filtrate, and enter the interstitial fluid, and then the bloodstream |
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Term
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Definition
some solutes are transported form the ISF across the tubular epithelium, into the flitrate |
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Term
What are the 3 comonents of filtration |
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Definition
1) fenestrated capillary
2) basement membrane
3) filtration slits |
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Term
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Definition
Endothelial cells with pores |
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Term
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Definition
contains large amounts of protein fibers |
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Term
Glomerular filtrate must cross three barriers to enter the Bowman's capsule, what are they |
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Definition
- Capillary endothelial cell layer
- Surrounding epithelia cell layer
- Basement membrane the is sandwiched between them
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Term
The amount of plasma the two kidneys receive over time is called the |
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Definition
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Term
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Definition
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Term
The __________ filtration rate is the rate at which filtrate is produced from plasma |
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Definition
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Term
What is the average glomerular filtration rate |
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Definition
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Term
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Definition
in the renal corpuscle
it is the bulk of flow of protein-free plasma from the glomerus into Bowman's capsule |
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Term
Where does reabsorption occur |
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Definition
along the tubules, is the movement of water or solute from the lumen of the tubules into the peritubular capillaries |
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Term
Where does secretion occur |
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Definition
along the tubules, it is the movement of solute from the peritubular capillaries into the lumen of the tubules |
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Term
Where is the juxtaglomerula appartus located |
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Definition
located where the initial part of the distal tubule passes through the fork between the afferent and efferent arterioles |
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Term
What does the juxtaglomerular apparatus do |
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Definition
regulating blood volume and blood pressure |
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Term
What do the secretory granules in the juxtaglomerular apparatus contain |
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Definition
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Term
Without regulation, blood pressure increases which would increase the ______, and decreases would decrease _______ |
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Definition
Glomerular Filtration Rate |
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Term
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Definition
- Increases MAP - stretchs the afferent arterioles
- constricts the smooth muscle in the afferent arterioles
- Decreases BP in the glomerular capillary bed
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Term
Tubuloglomerular feedback |
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Definition
- increased fluid flow past the macula densa
- releases paracrine signals
- constriction of the afferent arteriole
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Term
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Definition
- similar to smooth muscle cells
- respond to increased bp (in a manner similar to myogenic regulation)
- affect the capillary bed surface area, to affect filtration rates
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Term
Active reabsorption of solutes |
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Definition
Solutes can be actively transported against their concentration gradients across either the basolateral membrane or the apical membrane |
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Term
Passive reabsorption of water |
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Definition
active transport increases the osmolarity of peritubular fluid and plasma, creating conditions that enable reabsorption of water via osmosis |
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Term
Almost all nutrients that were in the filtrate are reabsorbed in the |
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Definition
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Term
How much of ions and water are reabsorbed in the PCT |
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Definition
65%
about 120 of the 180 liter of filtrate per day |
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Term
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Definition
this region of the tubule is impermeable to water and most solutes
But Na+, K+, and C1- are actively transported out of the ascending limb (reabsorption) |
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Term
Medullary Osmotic gradient |
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Definition
makes extensive water reabsorption possible in the descending limb and collecting duct
The descending limb of the loop of Henle is permeable to water, whereas the thick ascending limb is impermeable to water and contains trasnporters for Na+, C1- and K+ |
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Term
Low osmolarity of fluid entering the DCT allows us to generate a very |
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Definition
diluted urine when the plasma osmoarity is too low as in over-hydrated |
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Term
The reabsorption in the DCT and collecting duct allows what |
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Definition
allows us to generage highly concentrated urine when plasma osmolarity is too high as in dehydration |
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Term
Water is drawn out of the descending limb by |
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Definition
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Term
What is the descending limb permeable to |
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Definition
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Term
How much filtrate water is reabsorbed in the descending limb |
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Definition
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Term
Does the fluid entering the ascending limb have a high osmolarity or low osmolarity |
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Definition
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Term
Countercurrent multiplier system |
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Definition
works to maintain the high osmolarity of the renal medulla by pumping ions out of the tubular fluid in the ascending limb
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Term
High osmolarity of the medulla draws water out of the |
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Definition
descending limb, which actually makes it even easier to remove ions from the ascending limb. |
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Term
Countercurrent refers to the |
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Definition
opposite directions of fluid flow in the descending and ascending limb by the reabsorption of water in the descending limb |
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Term
DCT and Collecting Duct are they impermeable or permeable to water and solutes |
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Definition
impermeable to water and solutes |
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Term
What instructs the DCT and collecting ducts to perform reabsorption or secretion |
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Definition
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Term
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Definition
some solutes ar transported from the ISF across the tubular epithelium, into the filtrate. |
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Term
Anti-diuretic hormone is secreted by what |
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Definition
- secreted by the hypothalamus
- ECF osmolarity - high - inceases ADH
- ECF osmolority - low - decreases ADH
- Blood Pressure - decreased - stimulates ADH
- Angiotensin II
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Term
How much filtrate volume is reabsorbed in the DCT and collecting ducts under the influence of ADH |
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Definition
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Term
If our plasma osmolarity is too high, the additional ADH will instruct the DCT and collecting ducts to |
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Definition
increase the amount of water that is reabsorbed, so that we may generate as little as 0.4 L/day of urine (as when we are dehydrated) |
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Term
When our plasma osmolarity is too low, the reduced ADH secretion will allow the DCT and collecting ducts to |
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Definition
decrease the amount of water reabsorbed, so that we may generate as much as 20 L/day of urine (as when we are over-hydrated) |
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Term
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Definition
regulates the rates of Na+ reabsorbion and K+ secretion |
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Term
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Definition
Secreted by cells in the cortex of the adrenal gland |
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Term
Aldosterone secretion in response to |
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Definition
- increased blood K+ levels
- decreased blood volume or blood pressure, indirectly through the RAAS system
- decreased blood Na+ levels, indirectly through the RAAS system
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Term
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Definition
- binds to intracellular hormone receptors, which stimulates synthesis of Na+/K+ pumps
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Term
How do the Na+/K+ pumps work |
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Definition
- pump Na+ out of the tubular epithelial cells into the ISF
- pump K+ into the tubular epithelial cells from the ISF
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Term
Binding of aldosterone to its receptor also leads to opening of |
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Definition
ion channels, and stimulates ion channel synthesis.
diffusion of the ions across the apical membrane is more rapid |
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Term
Aldosterone facilitates Na+ reabsorption to maintain |
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Definition
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Term
Aldosterone facilitates K+ secretion to |
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Definition
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Term
The RAAS System
(renin-angiotensin-aldosterone system) |
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Definition
The liver and the juxtaglomerular cells secrete and release angiotensinogen and renin into the blood where renin cleaves amino acids from angiotensinogen to form angiotensinI.
Angiotensin convertng enzyme (ACE) located on certain endothelial cells in capillaries cleaves amino acids from angiontensin I to form angiotensin II, which travels in the bloodstream to the adrenal cortex, where it stiumulates the release of aldosterone into the blood. |
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Term
The liver and the juxtaglomerular cells secrete and release angiotensinogen and renin into the blood where |
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Definition
renin cleaves amino acids from angiotensinogen to form angiotensinI. |
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Term
Angiotensin convertng enzyme (ACE) located on certain endothelial cells in capillaries cleaves amino acids from angiontensin I to |
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Definition
form angiotensin II, which travels in the bloodstream to the adrenal cortex, where it stiumulates the release of aldosterone into the blood. |
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Term
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Definition
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Term
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Definition
an enzyme that converts angiotensin I to angiotensin II |
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Term
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Definition
a hormone the maintains and increases blood pressure
- stimulates vasoconstriction of systemic arteries (increase MAP)
- stimulates adreanl cortex to secrete aldosterone
- stimulates posterior pituitory to secrete ADH
- stimulates feelings of thirst in hypothalamus
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Term
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Definition
Na+ reabsorption, which in turn increases water reabsorption (prevents decreases in MAP) |
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Term
Posterior pituitary Gland secretes ADH |
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Definition
which increases wate reabsorption (prevents decreases in MAP) |
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Term
If Na+ is low will blood osmolarity be low |
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Definition
Yes, reduces ADH secretion, and leads to wate loss to that the body can maintain osmotic balance.
Water loss reduces MAP. Decreased MAP activates the RAAS system above to maintain MAP and increase Na+ reabsorption |
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Term
Atrial Natriuritic Peptide |
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Definition
works to decrease blood Na+ levels, and therefore decrease MAP |
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