Eukaryotic Diatoms. Photo: Wikipedia, Public domain Small Creatures with a Big Impact Understanding the ocean's carbon fixation cycle is extremely important if we are to better understand how CO2 emissions affect the global climate. Until recently, it was thought that cyanobacteria overwhelmingly accounted for phytoplankton's role in carbon sequestration in the ocean. Cyanobacteria, like all bacteria, are prokaryotes (they don't have a nucleus). Another less common type of phytoplankton is bigger and eukaryot...Read the full story on TreeHugger