Explain the text of the semon lee
Answers
(Top) The flagellar beat is asymmetric in 3D, characterized by a one-sided stroke in each beating plane that rotates with the flagellum. The out-of-plane motion causes the sperm flagellum to roll around the swimming axis (dark blue axis), causing the sperm to move equally on all sides in 3D. This creates the effect of a precessing spinning top, in which head spinning, ωspin, around the longitudinal axis of the sperm (yellow axis) occurs at the same time as, and independently of, the flagellar rolling, ωroll, around the swimming axis (Supporting Video S2). (Bottom) Planar projection of the 3D beat averages out the one-sided asymmetric stroke and creates the optical illusion of bilateral symmetry in 2D microscopy. Symmetry is thus achieved through asymmetry.