9/13/26, 4:00 AM EXAM THREE ch 37/38 Structure and Function of the Renal and Urologic Systems Flashcards | Quizlet
In the distal tubule, which cells reabsorb sodium and water, ✅ c. Principal.
as well as secrete potassium?
a. Distal Explanation
b. Proximal Principal cells reabsorb sodium and water and secrete potassium. Intercalated cells
c. Principal secrete either hydrogen or bicarbonate and reabsorb potassium. Distal and proximal
d. Intercalated refer to the tubules.
The distal convoluted tubule and the collecting duct contain two primary types of
specialized cells that fine-tune the final composition of urine. Principal cells are the
most abundant and perform the following critical functions:
(1) Sodium and Water Reabsorption: They respond to the hormone aldosterone,
which triggers the reabsorption of sodium ( 𝑁𝑎+). This creates an osmotic gradient
that allows water to follow (regulated by ADH).
(2) Potassium Secretion: As sodium is reabsorbed into the blood, principal cells
secrete potassium (𝐾+) into the tubular lumen to be excreted in the urine.
Why other options are incorrect
❌ a. Distal: While these cells are located in the distal tubule, "distal" is a location
descriptor, not the specific name of the functional cell type.
❌ b. Proximal: These cells are located in the proximal convoluted tubule at the
beginning of the nephron. While they reabsorb the bulk of sodium and water (about
65%), they do not perform the hormonal fine-tuning of potassium secretion seen in
the distal segments.
❌ d. Intercalated: These cells are also found in the distal tubule and collecting duct,
but their primary job is acid-base balance. They secrete hydrogen ions (𝐻+) and
reabsorb bicarbonate (𝐻𝐶𝑂−3) or potassium, depending on the body's pH needs.
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,9/13/26, 4:00 AM EXAM THREE ch 37/38 Structure and Function of the Renal and Urologic Systems Flashcards | Quizlet
2. Which muscle lies between the two openings of the ✅ c. Trigone.
ureter and urethra?
a. Micturition Explanation
b. Detrusor The trigone is a smooth triangular area in the bladder that lies between the openings
c. Trigone of the two ureters and the urethra. The detrusor muscle distends as the bladder fills
d. Urethra with urine and is made up of smooth muscle fibers that weave around the bladder
bag.
The trigone is a smooth, triangular-shaped region located at the base of the bladder.
Its boundaries are defined by three points:
The two openings of the ureters (where urine enters the bladder).
The single opening of the urethra (where urine exits the bladder).
The trigone is clinically significant because it is more rigid than the rest of the
bladder and does not expand as much during filling. It also acts as a "funnel" to direct
urine into the urethra and is a common site for infections (cystitis) to persist.
Why other options are incorrect
❌ a. Micturition: This is not a muscle; it is the medical term for the act of urinating
(voiding).
❌ b. Detrusor: This is the name of the entire smooth muscle layer that forms the wall
of the bladder. While the trigone is technically a part of the bladder floor, the
"Detrusor" refers to the broad muscle that contracts to empty the bladder.
❌ d. Urethra: This is the tube that carries urine from the bladder to the outside of the
body, rather than a muscle located between the openings.
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,9/13/26, 4:00 AM EXAM THREE ch 37/38 Structure and Function of the Renal and Urologic Systems Flashcards | Quizlet
3. Which statement is true regarding renal blood flow? ✅ a. The kidneys receive 1000-1200 mL of blood per minute.
a. The kidneys receive 1000-1200 mL of blood per minute.
b. The kidneys receive 50% of cardiac output. Explanation
c. The glomerular filtration rate (GFR) is not related to renal The kidneys are vascular organs and receive 1000-1200 mL of blood per minute and
blood flow. 20% to 25% of cardiac output. The GFR is related to renal blood flow, and
d. No autoregulation is found in renal blood flow. autoregulation is found in renal blood flow.
The kidneys are highly vascular organs that require a significant volume of blood to
perform their filtration functions.
Total Volume: In a healthy adult, the renal blood flow (RBF) is approximately 1000 to
1200 mL per minute.
Renal Plasma Flow: Since blood is composed of both cells and plasma, the actual
renal plasma flow (RPF)—which is the portion available for filtration—is about 600 to
700 mL per minute.
Significance: This high flow rate ensures that the entire plasma volume can be filtered
by the kidneys approximately 60 times per day.
Why other options are incorrect
❌ b. The kidneys receive 50% of cardiac output: This is an overestimation. The
kidneys typically receive about 20% to 25% of the total cardiac output. While this is a
massive amount for their size, it is not half of the heart's total output.
❌ c. The glomerular filtration rate (GFR) is not related to renal blood flow: GFR is
directly related to renal blood flow. As blood flow (and therefore hydrostatic
pressure) in the glomerular capillaries increases, the GFR generally increases as well.
❌ d. No autoregulation is found in renal blood flow: This is false. The kidneys
possess a very efficient autoregulatory mechanism (via the myogenic response and
tubuloglomerular feedback) that maintains a constant RBF and GFR even when
systemic blood pressure fluctuates between 80 and 180 mmHg.
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In the distal tubule, which cells reabsorb sodium and water, ✅ c. Principal.
as well as secrete potassium?
a. Distal Explanation
b. Proximal Principal cells reabsorb sodium and water and secrete potassium. Intercalated cells
c. Principal secrete either hydrogen or bicarbonate and reabsorb potassium. Distal and proximal
d. Intercalated refer to the tubules.
The distal convoluted tubule and the collecting duct contain two primary types of
specialized cells that fine-tune the final composition of urine. Principal cells are the
most abundant and perform the following critical functions:
(1) Sodium and Water Reabsorption: They respond to the hormone aldosterone,
which triggers the reabsorption of sodium ( 𝑁𝑎+). This creates an osmotic gradient
that allows water to follow (regulated by ADH).
(2) Potassium Secretion: As sodium is reabsorbed into the blood, principal cells
secrete potassium (𝐾+) into the tubular lumen to be excreted in the urine.
Why other options are incorrect
❌ a. Distal: While these cells are located in the distal tubule, "distal" is a location
descriptor, not the specific name of the functional cell type.
❌ b. Proximal: These cells are located in the proximal convoluted tubule at the
beginning of the nephron. While they reabsorb the bulk of sodium and water (about
65%), they do not perform the hormonal fine-tuning of potassium secretion seen in
the distal segments.
❌ d. Intercalated: These cells are also found in the distal tubule and collecting duct,
but their primary job is acid-base balance. They secrete hydrogen ions (𝐻+) and
reabsorb bicarbonate (𝐻𝐶𝑂−3) or potassium, depending on the body's pH needs.
https://quizlet.com/1150596074/exam-three-ch-3738-structure-and-function-of-the-renal-and-urologic-systems-flash-cards/?funnelUUID=e3d73caa-44c9-435a-ac7a-9969d0e0852a 3/98
,9/13/26, 4:00 AM EXAM THREE ch 37/38 Structure and Function of the Renal and Urologic Systems Flashcards | Quizlet
2. Which muscle lies between the two openings of the ✅ c. Trigone.
ureter and urethra?
a. Micturition Explanation
b. Detrusor The trigone is a smooth triangular area in the bladder that lies between the openings
c. Trigone of the two ureters and the urethra. The detrusor muscle distends as the bladder fills
d. Urethra with urine and is made up of smooth muscle fibers that weave around the bladder
bag.
The trigone is a smooth, triangular-shaped region located at the base of the bladder.
Its boundaries are defined by three points:
The two openings of the ureters (where urine enters the bladder).
The single opening of the urethra (where urine exits the bladder).
The trigone is clinically significant because it is more rigid than the rest of the
bladder and does not expand as much during filling. It also acts as a "funnel" to direct
urine into the urethra and is a common site for infections (cystitis) to persist.
Why other options are incorrect
❌ a. Micturition: This is not a muscle; it is the medical term for the act of urinating
(voiding).
❌ b. Detrusor: This is the name of the entire smooth muscle layer that forms the wall
of the bladder. While the trigone is technically a part of the bladder floor, the
"Detrusor" refers to the broad muscle that contracts to empty the bladder.
❌ d. Urethra: This is the tube that carries urine from the bladder to the outside of the
body, rather than a muscle located between the openings.
https://quizlet.com/1150596074/exam-three-ch-3738-structure-and-function-of-the-renal-and-urologic-systems-flash-cards/?funnelUUID=e3d73caa-44c9-435a-ac7a-9969d0e0852a 4/98
,9/13/26, 4:00 AM EXAM THREE ch 37/38 Structure and Function of the Renal and Urologic Systems Flashcards | Quizlet
3. Which statement is true regarding renal blood flow? ✅ a. The kidneys receive 1000-1200 mL of blood per minute.
a. The kidneys receive 1000-1200 mL of blood per minute.
b. The kidneys receive 50% of cardiac output. Explanation
c. The glomerular filtration rate (GFR) is not related to renal The kidneys are vascular organs and receive 1000-1200 mL of blood per minute and
blood flow. 20% to 25% of cardiac output. The GFR is related to renal blood flow, and
d. No autoregulation is found in renal blood flow. autoregulation is found in renal blood flow.
The kidneys are highly vascular organs that require a significant volume of blood to
perform their filtration functions.
Total Volume: In a healthy adult, the renal blood flow (RBF) is approximately 1000 to
1200 mL per minute.
Renal Plasma Flow: Since blood is composed of both cells and plasma, the actual
renal plasma flow (RPF)—which is the portion available for filtration—is about 600 to
700 mL per minute.
Significance: This high flow rate ensures that the entire plasma volume can be filtered
by the kidneys approximately 60 times per day.
Why other options are incorrect
❌ b. The kidneys receive 50% of cardiac output: This is an overestimation. The
kidneys typically receive about 20% to 25% of the total cardiac output. While this is a
massive amount for their size, it is not half of the heart's total output.
❌ c. The glomerular filtration rate (GFR) is not related to renal blood flow: GFR is
directly related to renal blood flow. As blood flow (and therefore hydrostatic
pressure) in the glomerular capillaries increases, the GFR generally increases as well.
❌ d. No autoregulation is found in renal blood flow: This is false. The kidneys
possess a very efficient autoregulatory mechanism (via the myogenic response and
tubuloglomerular feedback) that maintains a constant RBF and GFR even when
systemic blood pressure fluctuates between 80 and 180 mmHg.
https://quizlet.com/1150596074/exam-three-ch-3738-structure-and-function-of-the-renal-and-urologic-systems-flash-cards/?funnelUUID=e3d73caa-44c9-435a-ac7a-9969d0e0852a 5/98
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