protozoa and green algae in waste water under the microscope.

screenshot astronomy space night star circle darkness galaxy earth light flower invertebrate universe nebula planet protozoa green algae waste water microscope education eukaryotic flora lab marine protozoans nucleus invisible food vacuole microscopy paramecium research phytoplankton fauna scientific protist protozoan etching species protista aquatic plankton organism laboratory microscopic pond cell microbiology micro microorganism freshwater macro biology nature background science pediastrum spirostomum intermedium xanthidium micrasterias