Analysis of apoptotic morphology of HeLa cells treated with R. officinalis (REO), C. longa (CEO), and Z. officinale (GEO) essential oils using the Annexin V assay. (A) Negative control: cell population without influence of treatment. (B) Positive control: cell population treated with camptothecin. (C, D, and E) Cell population exposed to treatment with 322.45 μg/mL of REO, CEO, and GEO. Analysis performed by fluorescence microscopy. Images taken at 10x magnification.