Herein, we determine conditions for increased vs decreased efficiency of a helical flagellum rotating in shear-thinning vs non-shear-thinning fluids. We show that, for high elasticity and low shear ...

With their slender tails, human sperm propel themselves through viscous fluids, seemingly in defiance of Newton's third law of motion, according to a recent study that characterizes the motion of ...

In other words, rolling enables a sperm to swim progressively even if the flagellum beats asymmetrically. Therefore, a rolling sperm swims stably along the nearby walls (wall-dependent navigation) and ...

The closest living relatives of animals, the choanoflagellates, display a polarized cell architecture (with an apical flagellum encircled by microvilli) that resembles that of epithelial cells and ...