Fig. 5. The majority of 3OMD-glucose absorption is passive, as indicated by the high ratio of apparent absorption rates for L-glucose and 3OMD-glucose. Assuming that absorption of L-glucose is passive whereas the absorption of 3OMD-glucose represents the sum of passive + mediated absorption, the ratio of the apparent absorption rates (L/D) indicates the proportion of 3OMD-glucose absorption that occurs via the passive pathway. The ratios were calculated from the apparent rates shown in Fig. 4, for measurements made under relatively nonsaturating conditions (filled squares, solid line), and for measurements made under relatively more saturating conditions (unfilled circles, broken line).