Final answer:
The OI number for Accu-chek II glucose testing is not provided, but these devices typically use glucose oxidase-colorimetric reactions to measure blood glucose levels and display the concentration value electronically.
Step-by-step explanation:
The OI number for the Accu-chek II glucose testing system is not specified in general. In modern electronic gadgets designed for the estimation of blood glucose levels, glucose oxidase-colorimetric reactions are typically used. These devices, like the Accu-chek II, operate by placing a drop of blood on a reagent pad which contains enzymes including glucose oxidase and peroxidase, as well as color indicators. As glucose is oxidized, a color change occurs, and the intensity of this change is proportional to the amount of glucose in the blood. A reflectance photometer or an amperometric system measures this change to display the blood glucose concentration value electronically.