ATI LPN
Test Questions Renal System Questions
Question 1 of 5
What does this NFP indicate?
Correct Answer: C
Rationale: A Net Filtration Pressure (NFP) of -10 mmHg is negative, indicating that the combined opposing forces (oncotic pressure of 25 mmHg and capsular hydrostatic pressure of 15 mmHg, totaling 40 mmHg) exceed the glomerular hydrostatic pressure (30 mmHg). Normally, NFP is positive (around 10 mmHg) to drive filtration. A negative value means no filtration occurs, as fluid is pushed back into the capillaries rather than filtered, making C the correct interpretation.
Question 2 of 5
8-15% of water reabsorbed in the distal convoluted tubule needs?
Correct Answer: B
Rationale: In the distal convoluted tubule (DCT) and collecting duct, 8-15% of filtered water is reabsorbed under the influence of antidiuretic hormone (ADH). ADH increases aquaporin-2 insertion, enhancing water permeability in the collecting duct, with some effect in late DCT. Aldosterone affects Naâº, and angiotensin II modulates GFR, but ADH drives this water reabsorption, making B correct.
Question 3 of 5
Most important buffering system is?
Correct Answer: C
Rationale: The bicarbonate buffer system (HCO₃â»/Hâ‚‚CO₃) is the most important in blood, rapidly neutralizing acids or bases via COâ‚‚ exhalation (lungs) and HCO₃⻠regulation (kidneys). It handles ~70% of extracellular buffering. Proteins (D) and phosphate (B) contribute less, and bone (A) is a long-term reserve, making C the primary system.
Question 4 of 5
During an assessment of a patient who sustained a head injury 24 hours ago, the medical-surgical nurse notes the development of slurred speech and disorientation to time and place. The nurse's initial action is to:
Correct Answer: B
Rationale: Slurred speech and disorientation 24 hours post-head injury suggest worsening neurological status (e.g., hematoma, edema), a medical emergency. Informing the neurosurgeon (B) ensures prompt evaluation and intervention, as this exceeds routine monitoring (A) or delay (D). Preparing for surgery (C) assumes a decision not yet made, making B the critical initial action.
Question 5 of 5
What is the primary function of glomerular filtration in the process of urine formation?
Correct Answer: C
Rationale: Glomerular filtration's primary function is filtering blood to form an initial filtrate (C), passing water, electrolytes, and waste into Bowman's capsule while retaining proteins and cells. Reabsorption (A) and ion transport (B) occur in tubules, and pH regulation (D) is a broader kidney role, making C the specific glomerular step.