$$\text{Net filtration pressure} = PH - \pi - P_{fluid}$$

$$\text{Excretion} = \text{Filtration} - \text{Reabsorption} + \text{Secretion}$$

Question 1

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

Accepted Answer

Synthesis of plasma proteins

Question 2

Which structure is the functional unit of the kidney responsible for filtration, reabsorption, and secretion?

Accepted Answer

Nephron

Question 3

A patient has a mean arterial blood pressure of 90 mm Hg. What is the expected effect on glomerular filtration rate (GFR)?

Accepted Answer

GFR will remain relatively constant due to autoregulation

Question 4

Which equation correctly describes the net filtration pressure in the glomerulus?

Accepted Answer

$$	ext{Net filtration pressure} = PH - \pi - P_{fluid}$$

Question 5

If the afferent arteriole constricts, what happens to GFR and renal blood flow?

Accepted Answer

Both GFR and renal blood flow decrease

Question 6

Which part of the nephron is primarily responsible for the isosmotic reabsorption of organic nutrients, ions, and water?

Accepted Answer

Proximal tubule

Question 7

A patient with diabetes mellitus has glucose in their urine. This is best explained by which concept?

Accepted Answer

Renal threshold for glucose has been exceeded

Question 8

Which of the following best describes the clearance of a substance that is freely filtered, not reabsorbed, and not secreted?

Accepted Answer

Clearance equals the glomerular filtration rate (GFR)

Question 9

Which process is defined as the movement of fluid from the blood into the lumen of the nephron?

Accepted Answer

Filtration

Question 10

Which cells in the juxtaglomerular apparatus detect NaCl in the filtrate and help regulate GFR?

Accepted Answer

Macula densa cells

Question 11

Which of the following is true regarding the composition of urine after it leaves the collecting duct?

Accepted Answer

Its composition does not change before excretion

Question 12

Which equation best describes the amount of a substance excreted by the kidneys?

Accepted Answer

$$	ext{Excretion} = 	ext{Filtration} - 	ext{Reabsorption} + 	ext{Secretion}$$

Question 13

Which of the following best describes the role of the internal and external sphincters in micturition?

Accepted Answer

Internal sphincter is smooth muscle, external sphincter is skeletal muscle

Question 14

Which of the following would most likely increase the glomerular filtration rate (GFR)?

Accepted Answer

Constriction of the efferent arteriole

Question 15

Which of the following substances is commonly used clinically to estimate GFR because it is freely filtered and only minimally secreted?

Accepted Answer

Creatinine

Question 16

A drug that blocks the Na+-K+-ATPase in the proximal tubule would have what effect?

Accepted Answer

Decrease sodium and glucose reabsorption

Question 17

Which of the following best describes the movement of water during reabsorption in the nephron?

Accepted Answer

Water follows solute reabsorption by osmosis

Question 18

Which pressure opposes filtration in the glomerulus?

Accepted Answer

Capsule fluid pressure

Question 19

Which of the following is a correct statement about secretion in the nephron?

Accepted Answer

It is the active movement of molecules from extracellular fluid into the nephron lumen

Question 20

A patient is given a substance that is freely filtered, not reabsorbed, and completely secreted. What will its renal clearance be compared to GFR?

Accepted Answer

Clearance will be greater than GFR

Chapter 19: The Kidneys – Structure, Function, and Physiology

Study Guide - Practice Questions