Fertilization is the process by which male and female gametes, and their respective haploid genomes,
fuse to form a single cell (the zygote) containing a complete diploid complement of genetic material
representative of each parent. The male gamete, the sperm, transduces an activation stimulus to the awaiting
female gamete, the egg (also, oocyte or ova), initiating a cascade of events collectively referred to as egg
activation. The mechanisms of this process are both complex and tightly coordinated in order to impart a high
level of fidelity necessary for initiation of embryonic development and propagation of the species. Although
mechanistic discrepancies of this event exist even between species of the same phyla, calcium is the predominant
driving force of egg activation in all species studied to date, and is responsible for promoting the resumption and
exit of meiosis and the initiation of the developmental program. This chapter will focus on recent discoveries of
the molecular mechanisms of egg activation with specific regard to the regulation of calcium signaling as it
appears in the oscillatory mammalian system.
