sentences:  Among these parasites are the "Toxoplasma gondii" that cause toxoplasmosis and "Isospora belli", which results in isosporiasis.This is the largest order in the class Conoidasida and contains those species that all undergo merogony (asexual), gametogony (sexual) and sporogony (spore formation) during their lifecycles.Nineteen families, three subfamilies, and 70 genera are recognised in this order.