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the simplest type of sexual process in unicellular organisms. In hologamy, special sex cells (gametes) are not formed; rather, entire unicellular organisms fuse. Hologamy is observed in some green algae (of the family Polyblepharidae) and in a number of lower fungi (from Ar-chimycetes). Sometimes the term “hologamy” is used to describe the fusion of entire protoplasts that leave the cell walls (for example, in the unicellular algae Conjugatae).