Section VII: Renal Physiology Flashcards
Chapter 41Glomerular Filtration
The major force favoring filtration across the glomerular capillary wall is the:
a. Oncotic pressure of the plasma
b. Oncotic pressure of the glomerular filtrate
c. Hydrostatic pressure of the blood
d. Hydrostatic pressure of the glomerular filtrate
C
The glomerular filtration rate (GFR) is the:
a. Volume of blood filtered by the kidneys per minute per kilogram of body weight
b. Volume of plasma filtered by the kidneys per minute per kilogram of body weight
c. Volume of urine produced by the kidneys per minute per kilogram of body weight
d. Volume of glomerular filtrate formed by the kidneys per minute per kilogram of body weight
D
In clinical practice, the GFR may be estimated by determining the rate of creatinine clearance. The rate of creatinine clearance is the:
a. Volume of plasma cleared of creatinine per minute per kilogram of body weight
b. Volume of glomerular filtrate formed per minute per kilogram of body weight
c. Weight of creatinine filtered from the blood per minute per kilogram of body weight
d. Weight of creatinine per volume of urine formed per minute per kilogram of body weight
A
The two major characteristics that determine whether a blood component is filtered or retained in the capillary lumen are its:
a. Molecular radius and molecular weight
b. Molecular radius and lipid solubility
c. Molecular radius and plasma concentration
d. Molecular radius and electrical charge
D
The GFR is increased by:
a. A low-protein meal
b. Afferent arteriolar constriction
c. Tubuloglomerular feedback
d. Release of atrial natriuretic peptide
e. Activation of the renin-angiotensin-aldosterone system
E
Chapter 42 Solute Reabsorption
Which segment of the renal tubule is responsible for the reabsorption of the bulk of filtered solutes?
a. Proximal tubule
b. Thin limbs of Henle’s loop
c. Thick ascending limb of Henle’s loop
d. Distal convoluted tubule
e. Collecting duct
A
The main driving force for the reabsorption of solutes from the
tubule fluid is:
a. Active transport of solutes across the apical plasma membrane.
b. Secondary active transport of solutes across the apical plasma membrane.
c. Active transport of Na+ from the tubule epithelial cell across the basolateral plasma membrane by the electrogenic Na+ channel.
d. Active transport of Na+ from the tubule epithelial cell across the basolateral plasma membrane by the Na+,K+ -ATPase pump.
D
Glucose is found in the urine of an animal when:
a. Glucose transporters in the proximal tubule are inhibited by furosemide.
b. Glucose secretion in the proximal tubule is stimulated by angiotensin II.
c. Glomerular filtration barrier is defective causing increased glucose in the tubule fluid.
d. Plasma glucose is elevated, increasing glucose concentration in the tubule fluid above the proximal tubule transport
capacity.
D
The ultimate rate of excretion of K+ in the urine is determined by the: (Choose all correct answers)
a. Concentration of K+in the glomerular filtrate.
b. Proximal tubule, which reabsorbs or secretes K+to meet the physiological requirements of the animals.
c. Thick ascending limb, where K+ secretion is enhanced by high plasma K+
concentrations.
d. Distal convoluted tubule, which not only secretes K+ during hyperkalemia, but also alters NaCl uptake and hence, distal
NaCl delivery and plasma aldosterone, in response to changes in extracellular K+
concentration, and thereby regulates K+
secretion in the collecting duct.
e. Collecting duct, where the rate of K+
secretion is regulated, and K+ reabsorption also occurs.
D E
Which of the following are effects of aldosterone on Na+ transport in the connecting segment and collecting duct?
a. Enhances the permeability of Na+
channels in the apical plasma membrane, thereby enhancing Na+ reabsorption.
b. Stimulates Na+,K+-ATPase activity in the basolateral plasma membrane, thereby enhancing Na+ reabsorption.
c. Reduces the Na+ permeability of the apical plasma membrane, thereby inhibiting Na+ reabsorption.
d. Reduces Na+,K+-ATPase activity in the basolateral plasma membrane, thereby inhibiting Na+reabsorption.
e. Increases the abundance of Na+
channels in the apical plasma membrane, thereby enhancing Na+ reabsorption.
A B E
Chapter 43 Water Balance
The bulk of filtered water is reabsorbed by which renal tubule segment?
a. Proximal tubule
b. Thin limbs of Henle’s loop
c. Thick ascending limb of Henle’s loop
d. Cortical collecting duct
e. Inner medullary collecting duct
A
The kidney responds rapidly to changing water requirements. The ability to quickly alter the rate of water excretion by greatly
concentrating or diluting the urine is the result of several factors. Which of the following does not contribute to this ability?
a. Generation of hypertonic medullary interstitium
b. Countercurrent flow and differential salt and water permeabilities in the thin limbs of Henle’s loop
c. Dilution of the tubule fluid by the thick ascending limb and the distal convoluted tubule
d. Responsiveness of the collecting duct to antidiuretic hormone (ADH)
e. ADH-regulated countercurrent flow and enhanced water permeability in the vasa recta
E
The hypertonic medullary interstitium is generated in large part by:
a. Active transport of Na+ by the straight portion of the proximal tubule.
b. Active reabsorption of Na+ by the water-impermeable, ascending thin limb of Henle’s loop.
c. Active reabsorption of Na+ by the water-impermeable, thick ascending limb of Henle’s loop.
d. Increase in water channels in the apical plasma membrane of collecting duct cells under the influence of ADH.
C
In dehydration, ADH is released, which reduces water excretion by:
a. Enhancing water reabsorption in the proximal tubules by stimulating Na+,K+
-ATPase.
b. Enhancing water reabsorption in the thick ascending limb by stimulating the insertion of aquaporin-2 water channels
into the apical plasma membrane.
c. Enhancing water reabsorption in the collecting duct by stimulating Na+,K+
-ATPase activity.
d. Enhancing water permeability in the collecting duct by stimulating the insertion of aquaporin-2 water channels into the apical plasma membrane.
D
In clinical situations, the excretion of dilute urine may be caused by all the following except:
a. Chronic renal disease
b. Glucocorticoid administration
c. ADH deficiency
d. Hypercalcemia
e. Acute renal hypoperfusion
E
