Compartmentalization is lost and the gametes from each gamont strain begin to pair and syngamy occurs forming zygotes within the gametocyst. This is the only time during the life cycle that diploid cells are found. The oocysts can be released when the earthworm dies and decays completing the cycle when another earthworm ingests the oocyst. The sporozoites are released in the gut of the earthworm where they migrate to the seminal vesicles and mature into trophozoites. The oocysts can also be transferred through the seminal ducts when earthworms are fertilizing their eggs.
Birds eating infected worms can also help disperse the oocysts.
The oocysts are unharmed in birds' digestive tracts and are passed through to the soil. The Monocystis only has a sexual life cycle. These terms should be the focus if the students are not familiar with these concepts. Many times there is more to something than meets the eye. Within the seminal vesicles of earthworms live Monocystis , parasitic protozoans.