FIG. 4.

Accumulation of betaine from choline by H. elongata in M63 at increasing osmolarities. Cells were grown overnight in the presence of [methyl-¹⁴C]choline and [³H]glucose. Samples were centrifuged and washed, and the accumulated radioactivity was measured by scintillation counting. Experiments (at both salt concentrations) were repeated twice, and the data correspond to means which on no occasion varied by more than 5%. conc, concentration.