Practice Questions

Question 1

In the distal tubule, which cells reabsorb sodium and water and secrete potassium?

Answer 1

Principal

Intercalated cells secrete hydrogen and reabsorb bicarbonate and potassium. Principal cells reabsorb sodium and water and secrete potassium. Distal and proximal cells refer to the tubules.

Question 2

Which muscle lies between the two openings of the ureter and urethra?

Answer 2

Trigone

The location described in the stem is that of the trigone muscle. The detrusor muscle distends as the bladder fills with urine and is composed of smooth muscle fibers that weave around the bladder bag. Micturition is another term for urination. Urethra is the term for the tube that connects the bladder to the outside of the body.

Question 3

Which statement regarding renal blood flow is correct?

Answer 3

The kidneys receive 1000-1200 ml of blood per minute.

The kidneys are vascular organs and receive 1000-1200 ml of blood per minute and 20-25% of cardiac output. The GFR is related to renal blood flow, and autoregulation is found in renal blood flow.

Question 4

When a patient experiences hypotension, which enzyme is primarily being released?

Answer 4

Renin

Renin is an enzyme released during hypotension. It starts a cascade of events that leads to the production of the angiotensin enzyme.

Question 5

The movement of fluids and solute from the tubular lumen to the peritubular capillary plasma is called:

Answer 5

Tubular reabsorption

Tubular reabsorption is the movement of fluids and solute from the tubular lumen to the peritubular capillary plasma. Ultrafiltration is the process of filtration across the glomerular capillaries to form a filtrate of protein-free plasma. Tubular secretion refers to substances moving from the plasma of the capillary to the tubular lumen. Excretion is the elimination of the substance in the final urine.

Question 6

Which substance controls final urine concentration?

Answer 6

Antidiuretic hormone

Antidiuretic hormone controls final urine concentration. It is secreted from the posterior pituitary and increases water permeability in the last segment of the distal tubule. Renin stimulates the renin-angiotensin-aldosterone system, which can increase systemic arterial pressure and change renal blood flow. Renin forms angiotensin I that is converted to angiotensin II, which stimulates the secretion of aldosterone. Urea is dissolved in the blood and is excreted by the kidneys.

Question 7

Which diagnostic finding would be found in a normal urinalysis?

Answer 7

Specific gravity 1.016 to 1.022

The pH is generally 5 to 6.5, the urine is light yellow, the specific gravity is 1.016 to 1.022, and no white or red blood cells are present.

Question 8

_________ cortical nephrons constitute approximately 85% of all nephrons.

Answer 8

Superficial

Nephrons are the functional unit of the kidney. The three types include superficial, midcortical, and juxtamedullary. The superficial cortical nephrons constitute approximately 85% of all nephrons.