A: Schematic diagram of the on-chip single-cell cultivation system for Chlamydomonas. B: Image analysis protocol. (top) Micrographs are acquired using the time-lapse recording. (middle) The micrograph is digitized and cell contours are determined by applying a threshold filter. (bottom) Cell volume is calculated from the cross-sectional area assuming axisymmetrical shape of Chlamydomonas cells.