Rhoptry

A rhoptry is a specialized secretoryorganelle found in Apicomplexa protozoan parasites. Rhoptries are club-shaped organelles connected by thin necks to the extreme apical pole of the parasite. These organelles, like micronemes, are characteristic of the motile stages of Apicomplexaprotozoans. They can vary in number and shape and contain numerous enzymes that are released during the process of host penetration. The proteins they contain are important in the interaction between the host and the parasite, including the formation of the parasitophorous vacuole (PV).