[³H]hypoxanthine incorporation after 4 hours and 24 hours of incubation of P falciparum cultures sustained with RBCs in different hydration states. The experimental protocol was similar to that indicated in Figure 4 except that [³H]hypoxanthine incorporation was measured at 4 hours (A), representing invasion efficiency, and 24 hours (B), reflecting invasion and parasite growth. Note the orders of magnitude difference in the ordinate scales between panels A and B. Panel C reports the [³H]hypoxanthine incorporation ratio (24 hours-4 hours)/4 hours, estimated from randomly paired samples. This ratio is assumed to reflect mainly parasite growth rate because the extent of [³H]hypoxanthine incorporation attributed to invasion at 4 hours is subtracted in the calculations. The right columns in each panel report [³H]hypoxanthine incorporation in untreated controls. Columns and error bars represent means and SDs of triplicate measurements.