A form of involving haploid nuclei as it occurs between certain protists as well as .

Conjugation occurs among various algae as well as , though process by which it occurs, including as in fungi, is not identical between these various species. In addition, conjugation as it occurs in eukaryotes differs from conjugation as that occurs in bacteria.

In ciliates it is particularly the that are exchange in the course of conjugation, that is, rather than the "working" or .