Complex sentence: Electron transfer is used in all respiratory functions as well as phototransfer is such a broad, common, as well as essential reaction within nature, Marcus's theory has become vital within the field of chemistry.
Split into simpler sentences: Electron transfer is used in all respiratory functions as well as photosynthesis. Due to fact that electron transfer is such a broad, common, as well as essential reaction within nature, Marcus's theory has become vital within the field of chemistry.