Ferredoxin is a protein molecule that functions as an electron carrier in various physiological processes, most notably in the transfer of electrons during photosynthesis. Synonyms for ferredoxin include iron-sulfur protein, iron-sulfur center, and electron transport protein. These terms all refer to the specific chemical composition of the protein, which contains iron and sulfur atoms in a particular configuration that enables it to efficiently transport electrons. Other related terms include redox protein, electron transport chain protein, and protein cofactor. Understanding the various synonyms for ferredoxin is essential for scientists studying photosynthesis and other biological processes that rely on electron transport reactions.