To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video Movie S6. Movie for Fig. 4E, showing cells near the equator in a spheroid photostimulated from 0.05 s on the time counter at the bottom left. The arrow indicates the cell in a white box in Fig. 4E. The movie is run at ×1/17 speed. Detergent-extracted Volvox model exhibits an anterior–posterior gradient in flagellar Ca2+ sensitivity Noriko Ueki, and Ken-ichi Wakabayashi PNAS. 2018. 115:E1061-E1068 DOI: 10.1073/pnas.1715489115 Download Original Video Browse All Videos »