Related by context. Frequent words. (Click for all words.) 53 alga 53 organism 52 Cyanobacteria 50 Microorganisms 49 Daphnia 49 protozoan 48 symbionts 48 microbe 47 microorganism 47 Toxoplasma 47 deplete oxygen 47 nonliving 47 organisms 46 bacterial spores 46 micro organism 46 microbes 46 anoxic 46 microscopic algae 46 hydrothermal vent 45 aquatic organisms 45 microorganisms 45 colonizes 45 biosphere 45 Microbial 44 aquatic habitats 44 amoebae 44 anaerobic bacteria 44 Bacterium 44 extremophiles 44 single celled 44 sea anemone 44 naturally occurring 44 archaea 43 Microbes 43 diatom 43 Bacteria 43 freshwater 43 Organisms 43 foraminifera 43 copepods 43 creatures 43 Bt toxin 43 gut microbes 43 arthropod 42 bacteria 42 pathogenic organisms 42 aquatic creatures 42 diatoms 42 oxygenating 42 single celled organisms 42 lifeforms 42 Carbon sequestration 42 aquatic ecosystem 42 microscopic organisms 42 myoglobin 42 Acidic 42 fungal spores 42 nitrogen fixing 42 Fungal 42 Archaea 42 harmful pathogens 42 Vibrio 42 bacterium 42 prokaryotes 42 multicellular organisms 41 cyanobacteria 41 sequestering carbon 41 species 41 flagellum 41 micro organisms 41 dinoflagellates 41 CO -2 41 microbial 41 parasitic worm 41 terrestrial ecosystems 41 marine organisms 41 ecosphere 41 hydrothermal vents 41 Photosynthesis 41 Prions 41 cyanobacterium 40 habitable planet 40 photosynthesize 40 biota 40 abiotic 40 amoeba 40 naturally occurring bacteria 40 genetic alteration 40 denitrification 40 humans 40 algae 40 seagrasses 40 asexual reproduction 40 Clostridium 40 mycobacteria 40 bacteria fungi 40 Evaporation 40 nanomachines 40 mammals 40 vertebrate species 40 biogenic