streptococcus pneumoniae. pneumococcus, pathogen. spherical gram-positive bacteria. morphology. microbiology

asporogenic bacilli bacteria bacterial bacteriology biological cell cells classification cocci coccus diplococcus disease endospores firmicutes flat flora form grampositive illustration infection inflammatory infographic isolated magnifier malignant medicine microbe microbiology microscope microscopic morbific morphology nosogenic organism pathogen pathogenic pathology pneumococcus pneumoniae science shape spherical spore streptococcaceae streptococci streptococcus study type vector