ATI LPN
NCLEX Questions on Renal System Questions
Question 1 of 5
Which cells of the JGA act as mechanoreceptors?
Correct Answer: B
Rationale: Juxtaglomerular (JG) cells, found in the walls of the afferent arterioles within the juxtaglomerular apparatus (JGA), serve as mechanoreceptors. They detect mechanical stretch caused by changes in blood pressure within the arteriole. When pressure drops, JG cells release renin to initiate the renin-angiotensin-aldosterone system (RAAS), increasing blood pressure and GFR. Macula densa cells, in contrast, are chemoreceptors sensing tubular fluid composition, while podocytes and intercalated cells have unrelated functions, confirming B as the correct choice.
Question 2 of 5
To measure renal plasma flow we will have to measure: Renal blood flow first?
Correct Answer: B
Rationale: Renal plasma flow (RPF) is measured directly using substances like para-aminohippuric acid (PAH), which is filtered and secreted, with clearance equaling RPF (around 625 ml/min). Renal blood flow (RBF) is then calculated from RPF using hematocrit: RBF = RPF / (1 - hematocrit). Measuring RBF first isn't required, making B (False) correct.
Question 3 of 5
Angiotensin II receptors are found in:
Correct Answer: C
Rationale: Angiotensin II receptors (AT1) are prominently found in the zona glomerulosa of the adrenal cortex, where they stimulate aldosterone release to increase Na⺠reabsorption and blood pressure. While present in renal arterioles, their key endocrine role is in the adrenal gland, not JG cells (A), macula densa (B), or intercalated cells (D), making C correct.
Question 4 of 5
In a man undergoing surgery, it was necessary to aspirate the contents of the upper gastrointestinal tract. After surgery, the following values were obtained from an arterial blood sample: pH 7.55, PCO2 52 mm Hg and HCO3- 40 mmol/l. What is the underlying disorder?
Correct Answer: C
Rationale: A pH of 7.55 (alkalosis), PCOâ‚‚ of 52 mmHg (elevated), and HCO₃⻠of 40 mmol/L (high) indicate metabolic alkalosis, likely from loss of gastric acid (Hâº) via aspiration, raising HCO₃â». Elevated PCOâ‚‚ reflects respiratory compensation (hypoventilation). Respiratory alkalosis (B) has low PCOâ‚‚, acidosis (A, D) has low pH, making C correct.
Question 5 of 5
Which statement by a patient demonstrates an accurate understanding about herbal supplements?
Correct Answer: D
Rationale: Herbal supplements lack standardization in the U.S. (D), as the FDA classifies them as dietary supplements, not drugs, leading to variable potency and quality. Herbs can interact with medications and other herbs (A), most aren't rigorously tested (B), and FDA regulation is minimal (C), making D the accurate understanding.