B.coli is the largest ciliated protozoon found in humans. Pigs, large primates and humans are the reservoir of the parasite. B.coli can cause a severe colitis with ulcerations like ameobiasis.
Trophozoites divide by binary fission within the submucosa.
Rectal biopsy can also provide specimens for diagnosis. 55 m. Cysts are mature when they have a complete wall.