Related by context. Frequent words. (Click for all words.) 68 protozoan 65 organism 62 unicellular 61 flagellum 61 single celled organism 61 flatworms 60 single celled 59 microorganism 58 T. gondii 58 micro organism 58 alga 58 prokaryotes 57 symbiont 57 Scientists theorize 57 organelle 56 organisms 56 microbe 56 Helicobacter 56 bacterium 56 Caenorhabditis elegans 56 haploid 56 Archaea 56 bacterial pathogen 55 planktonic 55 single celled organisms 55 herpes viruses 55 bacilli 55 reproduce asexually 55 Toxoplasma 55 fungal pathogen 55 ribozyme 55 parasitic worms 55 mutant strain 55 diatom 54 protozoa 54 gut microbes 54 morphologically 54 eukaryotic 54 eukaryotic cells 54 riboswitch 54 nematode worms 54 amoebas 54 methanogens 54 Wolbachia 54 Bacillus subtilis 54 TB bacterium 54 chloroplasts 54 fluorescently labeled 53 parasitic worm 53 staphylococci 53 self replicating 53 Y. pestis 53 virions 53 ribozymes 53 symbionts 53 multicellular organisms 53 vertebrate animals 53 microbial ecology 53 microbiota 53 poxvirus 53 motile 53 genetic alteration 53 Saccharomyces cerevisiae 52 amoebae 52 Mycobacterium 52 mutant proteins 52 prion proteins 52 fibroblast cells 52 bacterial genome 52 vertebrate species 52 phylum 52 mycobacterium 52 multicellular 52 Plasmodium 52 Toxoplasma gondii 52 erythrocytes 52 evolutionary origins 52 defensins 52 amino acid sequence 52 biogenesis 52 phyla 52 Clostridium 52 filamentous 52 lentivirus 52 vacuoles 52 synthetic genome 52 gene splicing 52 porphyrins 52 mycobacteria 52 Anopheles gambiae 51 mutant strains 51 clades 51 archaea 51 chloroplast 51 roundworms 51 retrovirus 51 Neu5Gc 51 RNA molecule 51 nanobacteria 51 lectins 51 sea anemone