All of the following are chemical buffers system, except?

Correct Answer: C

Rationale: Chemical buffer systems neutralize H⁺ instantly: phosphate (HPO₄²⁻/H₂PO₄⁻), bicarbonate (HCO₃⁻/H₂CO₃), and proteins (e.g., hemoglobin). The respiratory system (C) regulates CO₂ via ventilation, a physiological mechanism, not a chemical buffer, acting over minutes, not instantly, making C the exception.

Correct Answer: B

Rationale: Adolescents (B) face peer pressure and busy schedules (e.g., school, sports), delaying voiding and risking habits like holding urine. Infants/toddlers (A) lack control, middle-aged adults (C) focus on work/health, and older adults (D) face physical issues, making B the group affected by these social factors.

Correct Answer: D

Rationale: Urea enters via filtrate (A), concentrates in cortical collecting ducts as water exits (B), and thin loops/medullary ducts allow urea recycling (C). All are true—filtrate supplies urea, water reabsorption concentrates it, permeable segments recycle it—making E (all are correct), reassigned as D, correct.

Correct Answer: B

Rationale: Deep breathing (B) relaxes the urinary sphincter and pelvic muscles, easing catheter insertion by reducing tension and resistance, especially in an anxious client. Initiating urine flow (A) is impractical during insertion and may complicate sterility, turning to the side (C) doesn't aid mechanically and risks contamination, and holding the labia or penis (D) is a nurse task to maintain sterility, not the client's, making B the effective facilitation method.

Correct Answer: B

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.