Question 1

Which of the following best describes the primary function of the nephron's proximal convoluted tubule (PCT)?

Accepted Answer

Reabsorption of glucose, amino acids, and the majority of Na+ and water from the filtrate

Question 2

A patient presents with a blood pH of 7.25 and elevated blood CO$$_2$$ levels. Which acid-base disorder is most likely present, and what is the primary compensatory mechanism?

Accepted Answer

Respiratory acidosis; renal compensation by increased HCO$$_3^-$$ reabsorption

Question 3

Which hormone increases the permeability of the collecting duct to water by stimulating the insertion of aquaporin-2 channels into the apical membrane?

Accepted Answer

Antidiuretic hormone (ADH)

Question 4

If the glomerular blood hydrostatic pressure (GHP) is 55 mmHg, the capsular hydrostatic pressure (CsHP) is 15 mmHg, and the blood colloid osmotic pressure (BCOP) is 30 mmHg, what is the net filtration pressure (NFP) at the glomerulus?

Accepted Answer

$$NFP = GHP - (CsHP + BCOP) = 55 - (15 + 30) = 10$$ mmHg

Question 5

Which of the following best explains why the kidneys are able to produce urine that is up to four times more concentrated than blood plasma?

Accepted Answer

The presence of a countercurrent multiplier system in the nephron loop and collecting duct

Question 6

A patient with chronic kidney disease is unable to excrete sufficient H$$^+$$ ions. What acid-base disorder are they most at risk for developing?

Accepted Answer

Metabolic acidosis

Question 7

Which of the following is a direct effect of aldosterone on the cells of the distal convoluted tubule (DCT) and collecting duct?

Accepted Answer

Increased reabsorption of Na$$^+$$ and secretion of K$$^+$$

Question 8

Which of the following buffer systems is most important for buffering changes in blood pH due to CO$$_2$$ fluctuations?

Accepted Answer

Carbonic acid-bicarbonate buffer system

Question 9

A marathon runner drinks excessive amounts of water without replacing electrolytes. Which condition is most likely to develop, and what is the primary risk?

Accepted Answer

Hyponatremia; risk of cellular swelling and neurological symptoms

Question 10

Which of the following best describes the mechanism by which antidiuretic hormone (ADH) increases water reabsorption in the collecting duct?

Accepted Answer

ADH stimulates the insertion of aquaporin-2 channels into the apical membrane of principal cells

Question 11

A patient is found to have a blood pH of 7.55 and a low partial pressure of CO$$_2. $$Which acid-base disorder is present, and what is a likely cause?

Accepted Answer

Respiratory alkalosis; hyperventilation

Question 12

Which of the following is NOT a function of the kidneys?

Accepted Answer

Production of insulin

Question 13

Which process is responsible for the movement of water from the filtrate back into the blood in the nephron?

Accepted Answer

Osmosis

Question 14

Which of the following would most likely result in an increased glomerular filtration rate (GFR)?

Accepted Answer

Dilation of the afferent arteriole

Question 15

Which of the following best describes the effect of atrial natriuretic peptide (ANP) on kidney function?

Accepted Answer

Decreases Na$$^+$$ reabsorption, leading to increased urine output

Question 16

A patient with severe diarrhea is losing large amounts of bicarbonate in their stool. What acid-base disorder are they at risk for, and what is the expected compensatory response?

Accepted Answer

Metabolic acidosis; respiratory compensation by hyperventilation

Question 17

Which of the following is a correct statement about the movement of sodium and potassium in the principal cells of the collecting duct, as shown in the first image?

Accepted Answer

Na$$^+$$ enters the cell from the tubule lumen via leakage channels and is actively transported into the interstitial fluid by the Na$$^+-K$^+$$ pump

Question 18

In the second image, which hormone is released in response to increased blood osmolarity and what is its effect on the kidneys?

Accepted Answer

Antidiuretic hormone (ADH); increases water reabsorption in the collecting duct

Urinary System and Fluid & Acid-Base Balance: Study Notes

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드