Electromagnetic bioeffects from relatively weak signals are often due to a time-varying electric field, induced by a time-varying magnetic field [1]. However, the ability of weak oscillating EMF fields to interact with liv­ing cells has been a source of controversy since thermal and other noise poses restrictions to the detection of weak signals by a cell. Activation of signal pathways by external stimuli connects the physical interactions of the applied EMF to the biological response [70]. In nonlinear systems such as biological sensory apparatus, presence of noise can actually en­hance the detection of weak signals, called stochastic resonance [84]. Very small changes in the underlying non-linear kinetics caused by very weak coherent signals and noise can lead to strong, but reversible alterations in the internal nonlinear processes and associated biological function such as ELF influences on G-protein activation dynamic, magnetic field influence on radical pair recombination reactions and weak signal amplification by stochastic resonance incorporated within the Ca2+ signal pathway models [70]. The mechanism of stochastic resonance has shown an amplification factor that may exceed a factor of 1,000. This is because in a nonlinear system, the reaction to an external signal may be much greater when act­ing as a whole than the response of the system’s individual elements. This resonance manifests itself by the appearance of sharp peaks in the power spectrum of the system at the driving frequency and in some of the higher harmonics. Currently, the cell membrane is considered the most likely cel­lular site for interactions with EMF’s and the possible role of ionic chan­nels of the membrane in the amplification process. The potential well-like structure of an ionic channel makes it the ideal system for stochastic reso­nance amplification [85].