Free Urinary System MCQs with Answers

• A. Glomerulus and Bowman capsule
• B. Proximal tubule and loop of Henle
• C. Distal tubule and collecting duct
• D. Renal pelvis and ureter

Explanation: The renal corpuscle consists of the glomerulus surrounded by Bowman capsule, where blood filtration begins.

• A. Proximal convoluted tubule
• B. Descending loop of Henle
• C. Distal convoluted tubule
• D. Collecting duct

Explanation: The proximal convoluted tubule performs extensive reabsorption of useful substances and water back into the blood.

• A. Reduced ADH release and dilute urine
• B. Increased ADH release and concentrated urine
• C. Reduced aldosterone release and concentrated urine
• D. Increased filtration and increased urine volume

Explanation: Dehydration stimulates ADH release, which increases water permeability in the late distal tubule and collecting ducts.

• A. Increasing sodium reabsorption and potassium secretion
• B. Increasing glucose filtration and calcium secretion
• C. Decreasing sodium reabsorption and potassium retention
• D. Blocking water reabsorption in collecting ducts

Explanation: Aldosterone promotes sodium reabsorption and potassium secretion mainly in the distal tubule and collecting duct.

• A. Glomerular filtration
• B. Tubular reabsorption
• C. Tubular secretion
• D. Urinary elimination

Explanation: Tubular secretion transfers selected substances from the blood into the nephron lumen for removal in urine.

• A. Increase the intravenous fluid rate
• B. Check the tubing for kinks and obstruction
• C. Administer a prescribed diuretic
• D. Remove the catheter and insert another

Explanation: The nurse first checks for a simple mechanical obstruction, such as a kinked tube or a bag positioned above the bladder.

• A. Excreting hydrogen ions and conserving bicarbonate
• B. Excreting bicarbonate and conserving hydrogen ions
• C. Reducing urea formation and retaining phosphate
• D. Increasing glucose secretion and reducing sodium loss

Explanation: The kidneys help correct acidosis by secreting hydrogen ions into tubular fluid and reabsorbing or generating bicarbonate.

• A. Moderate dilation of the afferent arteriole
• B. Moderate constriction of the afferent arteriole
• C. Increased permeability of the filtration membrane
• D. Increased blood flow into the glomerulus

Explanation: Constriction of the afferent arteriole reduces blood flow and pressure entering the glomerulus, so filtration falls.

• A. It creates a medullary gradient that supports water conservation
• B. It stores urine before voluntary bladder emptying
• C. It filters plasma before it enters Bowman capsule
• D. It prevents sodium movement throughout the nephron

Explanation: The loop of Henle contributes to the medullary concentration gradient through different water and solute permeabilities in its limbs.

• A. Filtration moves substances from tubules into the blood
• B. Reabsorption returns selected substances to the blood
• C. Secretion moves all plasma proteins into urine
• D. Excretion occurs before filtration in the nephron

Explanation: Tubular reabsorption returns needed water and solutes from the tubular fluid to the blood.

• A. Glomerulus, distal tubule, proximal tubule, collecting duct
• B. Bowman capsule, proximal tubule, loop of Henle, distal tubule
• C. Proximal tubule, Bowman capsule, distal tubule, loop of Henle
• D. Bowman capsule, loop of Henle, proximal tubule, collecting duct

Explanation: Filtrate enters Bowman capsule after passing through the glomerulus, then flows through the proximal tubule, loop of Henle, distal tubule…

• A. The ureter contains a wide internal lumen
• B. The ureter enters the bladder obliquely
• C. The ureter has a continuous external sphincter
• D. The ureter is lined by simple squamous epithelium

Explanation: The ureter passes obliquely through the bladder wall, so bladder pressure compresses it during filling and urination.

• A. It decreases water permeability in collecting ducts
• B. It increases water permeability in collecting ducts
• C. It prevents sodium filtration at the glomerulus
• D. It increases glucose secretion into tubular fluid

Explanation: Antidiuretic hormone increases water permeability in the late distal tubule and collecting ducts by promoting aquaporin insertion.

• A. Encourage the patient to drink more water
• B. Place the patient on cardiac monitoring and notify the provider
• C. Ask the patient to walk to improve renal circulation
• D. Document the result and repeat it at the next routine check

Explanation: Severe hyperkalaemia with ECG changes can cause life-threatening cardiac dysrhythmias, so circulation and cardiac monitoring take…

• A. Sodium ions
• B. Water molecules
• C. Large plasma proteins
• D. Small glucose molecules

Explanation: The filtration barrier normally prevents most large plasma proteins from entering the filtrate.

• A. The pain is caused by stretching of the renal capsule
• B. The pain results from spasms and distension of the ureter
• C. The pain is caused by irritation of the urinary sphincter
• D. The pain results from overfilling of the urinary bladder

Explanation: A stone can obstruct the ureter, causing smooth muscle spasm and distension above the obstruction.

• A. Urine volume increases and urine becomes dilute
• B. Urine volume decreases and urine becomes concentrated
• C. Urine volume increases and urine becomes concentrated
• D. Urine volume remains unchanged and urine becomes dilute

Explanation: Higher antidiuretic hormone levels increase water reabsorption from the collecting ducts.

• A. Renal pelvis
• B. Ureter
• C. Urinary bladder
• D. Renal cortex

Explanation: The urinary bladder is a muscular reservoir that stores urine until micturition occurs.

• A. The urine is pale yellow in colour
• B. The patient reports mild thirst
• C. The urine output remains markedly reduced
• D. The patient asks when oral fluids can restart

Explanation: Persistent urine output below about 0.5 mL/kg/hour may indicate reduced renal perfusion, obstruction or acute kidney injury and should be…

• A. It moves substances from blood into the nephron lumen
• B. It returns useful substances from tubular fluid to the blood
• C. It forms the initial filtrate from plasma in the glomerulus
• D. It moves urine from the kidneys into the urinary bladder

Explanation: Tubular reabsorption returns water and needed substances such as glucose, amino acids and selected electrolytes from tubular fluid to the…