Exam 3 with answers Flashcards
An increase in plasma potassium concentration causes the release of
aldosterone
What primarily acts to increase sodium channels in the luminal membrane of the principal cells of the collecting duct?
aldosterone
What are surrounded by peritubular capillaries that carry approximately 90% of the renal blood supply?
cortical nephrons
What produces 1,25-dihydroxy vitamin D3 (calcitriol)
kidneys
The normal renal plasma flow rate is _____ ml/minute
125
What includes:
- Filtration from the glomerular capillaries into the Bowman’s capsule
- secretion from peritubular capillaries into the tubular lumen
- reabsorption from tubules into peritubular capillaries
basic renal processes
The amount of potassium that is exreted in the urine is the result of potassium being: (3)
- filtered
- reabsorbed
- and secreted
These release paracrines that regulate the resistance in the afferent arteriole of the nephron
the cells of the macula densa
This changes as the filtrate passes through the tubule
the composition of the glomerular filtrate
If the hydrostatic pressure in the glomerular capillaries - 65 mmHg the oncotic pressure in the glomerular capillaries = 29 mmHg and the hydrostatic pressure in Bowman’s space = 16 mmHg, the glomerular filtration pressure is ___ mmHg
20
Most of the filtered calcium load is reabsorbed in the :
proximal tubule
The kidneys help restore a fall in plasma Ca concentration by
producing 1,25 dihydroxyvitamin D3 (calcitriol)
The principal cells of the cortical collecting duct respond to aldosterone by increasing the number and open time of luminal ENaC channels. True or false?
false
The principal cells of the cortical collecting duct respond to aldosterone by increasing the number of basolateral H/K-ATPases. True or false?
false
The principal cells of the cortical collecting duct respond to aldosterone by increasing the number and open time of luminal calcium channels. True or false?
false
Loop diurectics at on the basolateral membrane of the cells of the thick acending limb of the loop of Henle to inhibit Na/K-ATPase activity. True or false?
false
Loop diuretics disrupt the medullary concentration gradient and cause the excretion of a large volume of 300 mOsm urine. True or false?
True
Loop diuretics inhibit the Na/K/2Cl cotransporter in the luminal membrane of the cells of the thick ascending limb of the loop of Henle. True or false?
true
Loop diuretics can cause hypokalemia and alkalosis. True or false?
true
______ sparing diuretics act by decreasing sodium reabsorption by principal cells in the cortical collecting duct.
Potassium
______ inhibiors act in the distal tubule to inhibit the Na-Cl cotransporter
Thiazide
Parathyroid hormone acts to cause an increase in _____ reabsorption.
calcium
Potassium secretion increases in responses to a decrease in plasm _____ ion concentration
potassium
What:
- have long loops of Henle that dip deep into the medulla
- generate and maintain the medullary interstitial concentration gradient
- are serviced by branches of the peritubular capillaries termed vasa recta
- have an afferent and efferent arteriole
juxtamedullary nephrons
______ _____ ____ cause acidosis because they block intracellular generation of hydrogen and bicarbonate in proximal tubule cells.
Carbonic anhydrase inhibitors
Among the following filtered substances, which is most completely reabsorbed in the renal tubule?
glucose
Most of the Na that is filtered in the glomerulus is reabsorbed in the ____ _____
proximal tubule
The tubule segment where reabsorption of Na is linked to secretion of hydrogen ions is the ____ ____
proximal tubule
The tubule segment where reabsorption of Na is linked to secretion of potassium ions is the ____ ___.
collecting duct
The tubule segment where reabsorption of Na is linked to absorption of amino acids is the ___ ___.
proximal tubule
The tubule segment where reabsorption of Na is linked to absorption of bicarbonate ions is the ____ ___
proximal tubule
The tubule segment where Na reabsorption is hormonally regulated is the ___ ___.
collecting duct
In the proximal tubule, primary active transport of Na ions occurs in the _____ _____
basolateral membrane
Which of the choices below is NOT involved (directly or indirectly) in the regulation of body sodium content:
erthropoietin
Vasopressin regulates plasma osmolarity. True or false?
true
Elevated plasma levels of vasopressin lead to an increased water permeability in the collecting duct. True or false?
true
Vasopressin can cause a higher urine osmolarity. True or false?
true
Vasopressin closes apical ENaC channels in the collecting duct. True or false?
False
Drinking a lot of water will cause a drop in the plasma vasopressin concentration. true or false
true
The renal clearance of glucose is ___
zero
The renal celarance of creatinine is slightly higher than ______ _____ ____ but much lower than glomerular plasma flow rate.
glomerular filtration rate
The renal clearance of bicarbonate is higher in severe ____ than severe ______
alkalosis
acidosis
At high plasma vasopressin levels, the urine osmolarity would be ____ than the plasma osmolarity.
higher
A function of filtered phosphate in the urine is to ____ urine pH against secreted _____ ions.
buffer
hydrogen
A function of filtered sulfate in the urine is to alkanize the urine. True or false?
false
The filtered sulfate has no impact on urine pH. True or false?
True
The way the kidney compensates for respiratory acidosis is by incompletely/completely reabsorbing and/or creating “new” ______.
completely
bicarbonate
Renal compensation for respiratory alkalosis ______ plasma ______ and/or CO2 levels
lowers
bicarbonate
Respiratory compensation for metabolic acidosis _____ plasma _____ and/or CO2 levels.
lowers
bicarbonate
Under a “normal” protein-containing diet, an individual’s urine is: ______ acidic and pH is approximately ____
slightly
6.0
What excretes metabolic waste products from the body?
kidneys
What is formed when monoiodotyrosine is linked to diiodotyrosine?
3,5,3 triiodothyronine
What works by elevating cyclic adenosine monophosphate concentration in the target cells?
thyroid stimulating hormone (TSH)
Suppose that a steroid hormone, Q, is pressent at a low concentration in plasma. If the concentration of Q doubles in plasma, both free and bound Q concentrations will ____.
increase
A new hormone called ghrelin was discovered. It is comprised of several amino acids. From this information we could reasonably surmise that ghrelin is stored within ____ _____ in its endocrine cell origin.
secretory granules
The half-life of thyroid hormones is determined by the fact that they are mostly bound in the plasma to _____ ______ globulin.
thryoud binding
TsH increases the release of T3 and T4 from the thyroid follicular cells by stimulating the iodide pump. True or false?
true
TSH increases the release of T3 and T4 from the thyroid follicular cells by stimulating the formation of pseudopodia which engulf and internalize colloid. True or false?
true
TSH increases the release of T3 and T4 from the thyroid follicular cells by stimulating the activity of thyroperoxidase. True or false?
true
What are released into the blood in the region of the median eminence?
hypothalamic releasing hormones
The advantages of the ____ ____ _____ vessels are that:
- releasing hormones are not diluted by being secreted into the general circulation
- the portal vessels provide the most direct route to the anterior pituitary
- the anterior pituitary gland cells are more quickly excited to secrete their hormones
hypothalamo-pituitary portal
A hormone synthesized in the hypothalamus and secreted into the blood perfusing the posterior pituitary is _____ _____ .
antidiuretic hormone
