Answer
The mismatch is in item "c."
It is one of the functions of the kidneys to rid the body of nitrogenous metabolic wastes --urea, uric acid and creatinine. But this function does not match with the pH (acid-base) regulating function:
The kidneys adjust pH by ridding the body of a range of acidic and basic substances:
The normal pH of body fluids is 7.35 to 7.45. If the pH of the blood falls out of this range, the kidneys function to make the necessary adjustments: The kidneys absorb excess bicarbonate ions and excrete H+ ions as is needed to maintain normal pH of the blood. If blood is acidic ( low pH), H+ ions are excreted and bicarbonate ions (HCO3-) are reabsorbed. If the blood is basic, H+ ions are not excreted and bicarbonate ions are not reabsorbed.
Normal urine is usually acidic--about pH 6 (5-7), but it can range from pH 4.5 to 7.8.
Work Step by Step
The kidneys secrete the hormone erythropoietin.(EPO). When blood oxygen concentration [O2]get too low, EPO is secreted from the kidneys. This hormone stimulates the red bone marrow to increase the production of red blood cells (RBC's). When the number of RBC's increases , the blood oxygen[O2] also increases.
The kidneys also function to excrete the nitrogenous waste substances of protein metabolism. These waste substances include urea, uric acid, and creatinine. Elevated blood levels of urea cause uremia; elevated levels of uric acid may result in gout.
