The fertilization dance: a mechanical view of the egg rotation during the initial spermatozoa-ovum interaction.
The motion of the ovum and the spermatozoa toward each other in the oviduct culminates in a meeting that ultimately results in fertilization. This encounter is characterized by a slow rotation of the sperms-egg cluster while the sperms attempt a penetration. The mysterious rotation was observed in vivo and in vitro for homologous and heterologous systems. It lacks a satisfactory biological explanation while it seems to be correlated with the efficiency of fertilization. A simple bio-mechanical model presented here predicts that the slow rotation of the sperms-egg cluster is a natural consequence of the encounter in most cases. A linear stability analysis of the system suggests a quantitative explanation of the rotation causes, its intensity and its direction. The entire encounter seems as a micro-scale process of courting of the ovum by the spermatozoa, which is expressed as circular dance.
Nir
Avinoam
A
Department of Chemical Engineering, Technion, Haifa 32000, Israel. avinir@tx.technion.ac.il
D001696:Biomechanical Phenomena; D006801:Humans; D008297:Male; D008954:Models, Biological; D009068:Movement; D010063:Ovum / Q000502:physiology*; D013084:Sperm-Ovum Interactions / Q000502:physiology*