Load Response of the Flagellar Beat

Phys Rev Lett. 2016 Dec 16;117(25):258101. doi: 10.1103/PhysRevLett.117.258101. Epub 2016 Dec 14.


Cilia and flagella exhibit regular bending waves that perform mechanical work on the surrounding fluid, to propel cellular swimmers and pump fluids inside organisms. Here, we quantify a force-velocity relationship of the beating flagellum, by exposing flagellated Chlamydomonas cells to controlled microfluidic flows. A simple theory of flagellar limit-cycle oscillations, calibrated by measurements in the absence of flow, reproduces this relationship quantitatively. We derive a link between the energy efficiency of the flagellar beat and its ability to synchronize to oscillatory flows.

MeSH terms

  • Chlamydomonas / physiology*
  • Cilia
  • Flagella / physiology*
  • Models, Biological*
  • Movement