$$\text{GFR} = \frac{\text{Urine concentration} \times \text{Urine flow rate}}{\text{Plasma concentration}}$$

Question 1

Which of the following is NOT a function of the urinary system?

Accepted Answer

Synthesis of erythropoietin to stimulate red blood cell production

Question 2

What is the primary function of the glomerulus in the nephron?

Accepted Answer

Filtration of blood plasma to form glomerular filtrate

Question 3

Which structure in the nephron is primarily responsible for the reabsorption of glucose, amino acids, and small peptides?

Accepted Answer

Proximal convoluted tubule (PCT)

Question 4

A patient with chronic hypertension is at increased risk for which of the following kidney complications?

Accepted Answer

Rupture of glomerular capillaries and renal failure

Question 5

Which of the following best describes the composition of glomerular filtrate as it enters the capsular space?

Accepted Answer

Contains water, electrolytes, glucose, amino acids, and small molecules

Question 6

If the glomerular filtration rate (GFR) is too high, what is the most likely consequence?

Accepted Answer

Dehydration and electrolyte depletion

Question 7

Which hormone is released by the kidneys in response to low blood pressure and initiates a cascade that increases blood pressure?

Accepted Answer

Renin

Question 8

What is the main effect of sympathetic nervous system activation on the kidneys?

Accepted Answer

Constriction of afferent arterioles to conserve water

Question 9

Which part of the nephron is most permeable to water due to its thin segment lined with simple squamous epithelium?

Accepted Answer

Thin descending limb of nephron loop

Question 10

A patient is found to have a GFR of 50 mL/min (normal: 105–125 mL/min). What is a likely consequence if this persists?

Accepted Answer

Accumulation of metabolic wastes in the blood

Question 11

Which of the following equations correctly represents the calculation of glomerular filtration rate (GFR)?

Accepted Answer

$$	ext{GFR} = \frac{	ext{Urine concentration} 	imes 	ext{Urine flow rate}}{	ext{Plasma concentration}}$$

Question 12

Which cells in the juxtaglomerular apparatus monitor the flow rate and osmolarity of the filtrate?

Accepted Answer

Macula densa cells

Question 13

Which of the following best describes the role of aldosterone in kidney function?

Accepted Answer

Promotes sodium and water reabsorption in the distal convoluted tubule

Question 14

Which of the following substances is NOT normally found in the glomerular filtrate?

Accepted Answer

Large plasma proteins

Question 15

A patient is given a drug that blocks the action of antidiuretic hormone (ADH). What is the expected effect on urine output?

Accepted Answer

Urine output will increase

Question 16

Which of the following best explains why the afferent arteriole is larger than the efferent arteriole in the glomerulus?

Accepted Answer

To create high hydrostatic pressure for filtration

Question 17

Which process is responsible for moving substances from the blood into the tubular fluid after filtration has occurred?

Accepted Answer

Tubular secretion

Question 18

Which of the following is a direct effect of angiotensin II on the kidneys?

Accepted Answer

Constriction of efferent arterioles to maintain GFR

Question 19

Which region of the nephron is the official site where urine is first present?

Accepted Answer

Collecting duct

Question 20

A patient with a mutation that causes defective podocytes would most likely experience which of the following?

Accepted Answer

Leakage of large proteins into the urine

The Urinary System: Structure, Function, and Regulation

Study Guide - Practice Questions