Biol 431 Lecture Exam 3 Questions
with Correct Answers
Bulk flow of nutrients, ions and water into the peritubular capillaries is the result of all
of the following except one. Select the answer below that does NOT describe a
cause of bulk flow of fluids into the peritubular capillaries.
a) increased resistance to blood flow at the efferent arteriole
b) leaky tight junctions of peritubular capillary's endothelium
c) higher osmotic pressure in the peritubular capillary - ANSWER-B
The mechanism that establishes the medullary osmotic gradient depends most on
the permeability properties of the ________.
a) glomerular filtration membrane
b) nephron loop
c) collecting duct - ANSWER-B
An increase in the permeability of the cells of the collecting tubule to water is due to
a(n) ________.
a) increase in the production of aldosterone
b) decrease in the production of ADH
c) increase in the production of ADH - ANSWER-C
The kidneys are stimulated to produce renin ________.
a) by a decrease in the blood pressure
b) when the specific gravity of urine rises above 1.10
c) when the pH of the urine decreases - ANSWER-A
The descending limb of the nephron loop ________.
a) contains fluid that becomes more concentrated as it moves down into the medulla
b) is freely permeable to sodium and urea
c) pulls water by osmosis into the lumen of the tubule - ANSWER-A
Select the correct statement about the ureters.
a) The ureters are capable of peristalsis like that of the gastrointestinal tract.
b) The epithelium is stratified squamous like the skin, which allows a great deal of
stretch.
c) Ureters contain sphincters at the entrance to the bladder to prevent the backflow
of urine. - ANSWER-A
,Which of the following does NOT describe the juxtaglomerular complex?
a) Its granular cells produce rennin.
b) Its macula densa cells produce aldosterone.
c) It regulates the rate of filtrate formation. - ANSWER-B
Which of the following acts as the trigger for the initiation of micturition (voiding)?
a) the sympathetic efferents
b) motor neurons
c) the stretching of the bladder wall - ANSWER-C
The mechanism of water reabsorption by the renal tubules is ________.
a) active transport
b) filtration
c) osmosis - ANSWER-C
The macula densa cells respond to ________.
a) changes in Na+ content of the filtrate
b) aldosterone
c) antidiuretic hormone - ANSWER-A
Alcohol acts as a diuretic because it ________.
a) inhibits the release of ADH
b) increases the rate of glomerular filtration
c) increases secretion of ADH - ANSWER-A
The direct function of angiotensin II is to ________.
a) decrease water absorption
b) constrict arterioles and increase blood pressure
c) decrease arterial blood pressure - ANSWER-B
Which of the following is incorrect?
a) The concentration of urine is lower when urine volume is reduced.
b) The kidneys produce a small volume of concentrated urine when dehydrated.
c) The kidneys produce a large volume of dilute urine when over-hydrated. -
ANSWER-A
Which of the choices below is a function of the nephron loop?
a) form a large volume of very dilute urine or a small volume of very concentrated
urine
b) absorb electrolytes actively and water by osmosis in the same segments
c) form a large volume of very concentrated urine or a small volume of very dilute
urine - ANSWER-A
, What is the effect of antidiuretic hormone on the cells of the collecting duct?
a) causes aquaporins to be inserted into the apical membranes
b) triggers synthesis of more sodium channels in the apical membranes
c) inhibits sodium reabsorption through the apical membranes - ANSWER-A
Which of the following hormones acting on the collecting duct is most responsible for
retaining sodium ions in the blood?
a) aldosterone
b) atrial natriuretic peptide
c) parathyroid hormone - ANSWER-A
Which of the choices below is NOT a method by which the cells of the renal tubules
can raise blood pH?
a) by producing new bicarbonate ions
b) by secreting hydrogen ions into the filtrate
c) by reabsorbing filtered bicarbonate ions
d) by secreting sodium ions - ANSWER-D
In the ascending limb of the nephron loop the ________.
a) thick segment moves ions out into interstitial spaces for reabsorption
b) thick segment is permeable to water
c) thin segment is freely permeable to water - ANSWER-A
Except for potassium ions, tubular secretion of most unwanted substances occurs in
the ________.
a) nephron loop
b) proximal convoluted tubule
c) collecting duct
d) distal convoluted tubule - ANSWER-B
Which of the choices below is the salt level-monitoring part of the nephron?
a) nephron loop
b) vasa recta
c) macula densa - ANSWER-C
Which of the hormones below is responsible for facultative water reabsorption?
a) atrial natriuretic peptide
b) ADH
c) aldosterone - ANSWER-B
Which of the choices below are the most important hormone regulators of electrolyte
reabsorption and secretion?
with Correct Answers
Bulk flow of nutrients, ions and water into the peritubular capillaries is the result of all
of the following except one. Select the answer below that does NOT describe a
cause of bulk flow of fluids into the peritubular capillaries.
a) increased resistance to blood flow at the efferent arteriole
b) leaky tight junctions of peritubular capillary's endothelium
c) higher osmotic pressure in the peritubular capillary - ANSWER-B
The mechanism that establishes the medullary osmotic gradient depends most on
the permeability properties of the ________.
a) glomerular filtration membrane
b) nephron loop
c) collecting duct - ANSWER-B
An increase in the permeability of the cells of the collecting tubule to water is due to
a(n) ________.
a) increase in the production of aldosterone
b) decrease in the production of ADH
c) increase in the production of ADH - ANSWER-C
The kidneys are stimulated to produce renin ________.
a) by a decrease in the blood pressure
b) when the specific gravity of urine rises above 1.10
c) when the pH of the urine decreases - ANSWER-A
The descending limb of the nephron loop ________.
a) contains fluid that becomes more concentrated as it moves down into the medulla
b) is freely permeable to sodium and urea
c) pulls water by osmosis into the lumen of the tubule - ANSWER-A
Select the correct statement about the ureters.
a) The ureters are capable of peristalsis like that of the gastrointestinal tract.
b) The epithelium is stratified squamous like the skin, which allows a great deal of
stretch.
c) Ureters contain sphincters at the entrance to the bladder to prevent the backflow
of urine. - ANSWER-A
,Which of the following does NOT describe the juxtaglomerular complex?
a) Its granular cells produce rennin.
b) Its macula densa cells produce aldosterone.
c) It regulates the rate of filtrate formation. - ANSWER-B
Which of the following acts as the trigger for the initiation of micturition (voiding)?
a) the sympathetic efferents
b) motor neurons
c) the stretching of the bladder wall - ANSWER-C
The mechanism of water reabsorption by the renal tubules is ________.
a) active transport
b) filtration
c) osmosis - ANSWER-C
The macula densa cells respond to ________.
a) changes in Na+ content of the filtrate
b) aldosterone
c) antidiuretic hormone - ANSWER-A
Alcohol acts as a diuretic because it ________.
a) inhibits the release of ADH
b) increases the rate of glomerular filtration
c) increases secretion of ADH - ANSWER-A
The direct function of angiotensin II is to ________.
a) decrease water absorption
b) constrict arterioles and increase blood pressure
c) decrease arterial blood pressure - ANSWER-B
Which of the following is incorrect?
a) The concentration of urine is lower when urine volume is reduced.
b) The kidneys produce a small volume of concentrated urine when dehydrated.
c) The kidneys produce a large volume of dilute urine when over-hydrated. -
ANSWER-A
Which of the choices below is a function of the nephron loop?
a) form a large volume of very dilute urine or a small volume of very concentrated
urine
b) absorb electrolytes actively and water by osmosis in the same segments
c) form a large volume of very concentrated urine or a small volume of very dilute
urine - ANSWER-A
, What is the effect of antidiuretic hormone on the cells of the collecting duct?
a) causes aquaporins to be inserted into the apical membranes
b) triggers synthesis of more sodium channels in the apical membranes
c) inhibits sodium reabsorption through the apical membranes - ANSWER-A
Which of the following hormones acting on the collecting duct is most responsible for
retaining sodium ions in the blood?
a) aldosterone
b) atrial natriuretic peptide
c) parathyroid hormone - ANSWER-A
Which of the choices below is NOT a method by which the cells of the renal tubules
can raise blood pH?
a) by producing new bicarbonate ions
b) by secreting hydrogen ions into the filtrate
c) by reabsorbing filtered bicarbonate ions
d) by secreting sodium ions - ANSWER-D
In the ascending limb of the nephron loop the ________.
a) thick segment moves ions out into interstitial spaces for reabsorption
b) thick segment is permeable to water
c) thin segment is freely permeable to water - ANSWER-A
Except for potassium ions, tubular secretion of most unwanted substances occurs in
the ________.
a) nephron loop
b) proximal convoluted tubule
c) collecting duct
d) distal convoluted tubule - ANSWER-B
Which of the choices below is the salt level-monitoring part of the nephron?
a) nephron loop
b) vasa recta
c) macula densa - ANSWER-C
Which of the hormones below is responsible for facultative water reabsorption?
a) atrial natriuretic peptide
b) ADH
c) aldosterone - ANSWER-B
Which of the choices below are the most important hormone regulators of electrolyte
reabsorption and secretion?
