A. True This raises plasma bicarbonate to compensate for the raised PCO2 in respiratory acidosis.
B. True In acidosis, tubular cells excrete more to buffer the additional H+ ions being secreted.
C. True The increased secretion of H+ ions in exchange for Na+ results in decreased secretion of K+ ions.
D. False The ratio decreases as hydrogen ions are taken up by the phosphate buffer system.
E. False The urine remains bicarbonate-free.