Answer to Question 1
ANS: D
The National Institute of Standards and Technology (NIST) and the International Federation of Clinical Chemistry (IFCC) have established standards for the calibration of blood gas electrodes. A one-point calibration uses a nearly normal pH buffer with a pH of 7.384. A second, lower pH buffer, pH 6.840 is analyzed in the two-point calibration to ensure that the electronic output of the electrode is linear over a wide range of pH levels.
Answer to Question 2
ANS: A
As a blood sample comes in contact with the measuring electrode of the glucose sensor, the glu-cose oxidase on the surface of the electrode converts the glucose in the sample to hydrogen per-oxide and gluconic acid.