Let me share with you a difference between apicomplexans and ciliates.
| Aspect | Apicomplexans | Ciliates |
| Characteristics
| · Unicellular with complex internal structures, including an apical complex · Apical complex, which includes specialized organelles for host cell invasion · Micronemes, rhoptries, and dense granules for host cell invasion | · Unicellular with cilia on the cell surface · Macronucleus and micronucleus; ciliates often have complex nuclear dimorphism · Oral groove for food intake, contractile vacuole for osmoregulation |
| Cilia | Lack cilia | Possess numerous cilia for locomotion and feeding |
| Mode of nutrition | Obligate intracellular parasites; often parasitize animals | Mostly free-living, some parasitic or symbiotic |
| Type of reproduction | Mostly asexual reproduction through schizogony (multiple fission) | Asexual (binary fission) and sexual reproduction (conjugation) |
| Type of habitat | Parasitic forms are often found in the host’s tissues | Aquatic environments, both freshwater and marine, as well as soil |
| Examples | · Plasmodium which causes malaria · Toxoplasma gondii which causes toxoplasmosis | · Paramecium · Tetrahymena · Stentor |