Membrane thickness varies across organelles. (A) Global per-triangle measurements across different organelle classes are mapped to the different organelle classes observed in a single tomogram from a lamella generated from a MEF cell. (B) Local per-triangle measurements across different organelle classes are mapped to the different organelle classes observed in a single tomogram from MEF. (C) Per-triangle median thickness histograms highlight the difference in thickness distributions between different physiological organelles in MEF. (D) Violin plot of per-surface median thickness reveals statistically significant differences in thickness between different organelles in MEF. IMM: n = 15; OMM: n = 15; ER: n = 12; vesicle: n = 7. P values from the Mann–Whitney U test are indicated. ****P < 0.001. (E) Global per-triangle measurements across different organelle classes are mapped to the different organelle classes observed in a single tomogram from yeast (S. cerevisiae). (F) Local per-triangle measurements across different organelle classes are mapped to the different organelle classes observed in a single tomogram from yeast cell lamellae. (G) Per-triangle median thickness histograms highlight the difference in thickness distributions between different physiological organelles in yeast cell lamellae. (H) Violin plot of per-surface median thickness reveals statistically significant differences in thickness between different organelles in yeast. IMM: n = 11; OMM: n = 11; ER: n = 11; plasma membrane: n = 9; vacuole: n = 6; vesicle: n = 5; nucleus: n = 5. P values from the Mann–Whitney U test are shown in the table. PM, plasma membrane.