An electrical model for the cytoplasmic calcium wave in fertilized eggs.

The calcium wave subsequent to fertilization of the egg is analyzed interms of an electrical equivalent circuit. The circuit consists of aswitch, capacitor, an inductor, and a resistor. The switch symbolizes aseries of chemical reactions initiated by the sperm the lead to thedevelopment of the calcium wave. Its closure signifies the onset of thecalcium wave. The capacitor and inductor represent the endoplasmicreticulum. The capacitive component of the endoplasmic reticulum controlsthe release of calcium ions while the inductive component regulates thesequestration of clacium ions. The resistor represents the inductor andcytoplasm and has very low resistance. The analysis of the circuit showsthat the period of the calcium oscillations is proportional to the size ofthe egg. It agrees with the measurements on various types of eggs.