unicellular organism: protozoan gliding across a droplet, reflecting the simplicity and complexity of primitive life

microbe plankton nucleus microorganism water zoology evolution aquatic structure ciliate amoeba cell flagella bacterium environment protozoan biology protist unicellular living disease exploration parasite infection microscopic biodiversity protozoon colony ecosystem specimen organism study nature flagellate protozoa science tiny natural species movement bacteria ecology singlecell life habitat eukaryote microscope pathogen research ai generated