they eat the material passing through
anaerobic.
Most synthesized by bacteria in the Large Intestine
Anaerobic bacteria or facultative anaerobic bacteria.
anaerobic
aerobic bacteria use oxygen based respiration, anaerobic bacteria use either nonoxygen based respiration (e.g. nitrogen, sulfur) or fermentation.
used for growth anaerobic bacteria
Salmonella bacteria are anaerobic.
Synthesis of Vitamin K and some B Vitamins
what are the cause is anaerobic respiration in bacteria and fungi
Aerobic bacteria uses oxygen for cellular respiration and anaerobic bacteria doesn't require oxygen to survive. ˇ_ˇ 
Some methanogenic bacteria (which are anaerobic) do have flagella. You can read more in the related link
Anaerobic means without oxygen. Those are anaerobic bacteria.