Figure 2. Membrane synthesis increases from G₂/M to G₁. The cells were synchronized by 2TB. (A) Cells were pulsed with [¹⁴C]choline for 2 h prior their harvesting, and the radioactivity associated to the lipid fraction was determined by scintillation counting and normalized to total protein content. (B) The total fatty acid content at G₁ (12 h), S (4 h), and G₂/M (8 h) was determined by gas chromatography using C23:0 as internal standard and normalized to cell number. The values are plotted as mean ± SD of a representative experiment. *P < 0.05 ANOVA and Tukey.