p. 199 - 211 EFFECT OF Cd2+ ON THE METABOLISM OF THE MARINE UNICELLULAR ALGAE Pia Elena Mihnea, Gheorghe Munteanu, Ion Pecheanu Romanian Marine Research Institute Constanta Abstract Some metabolic modifications of Chaetoceros simplex v. calcitrans Pauls., Cyclotella caspia Grun., Skeletonema costatum Grev., Chlamydomonas sp. and Platymonas impellucida McLaughlan & Parke, which occured under the influence of Cd2+ are analysed. The specificity of Cd2+ on different algae has been demonstrated and the mechanism of their protection against Cd2+ effect has been explained.