Marine viruses, bacteria and a diatom. SYBR® Green I nucleic acid stain.
An environmental sample containing marine viruses (smallest dots), bacteria (larger, brighter dots), and a diatom (long thin cell with prominent nucleus) stained with SYBR® Green I nucleic acid stain (Cat. no. S7563, S7567, S7585). Image contributed by Jed Fuhrman, University of Southern California.