Sexual Reproduction - Conjugation occurs in many bacteria and Actinomycetes, including Streptomyces. Conjugation leads to the formation of, usually, partial diploids in which crossing over produce recombinant genotypes. Recombinants are recovered and used for genetic studies like linkage mapping.

Similarly, yeast has .two mating types; the cells of opposite mating types fuse to form diploid heterozygous cells. The diploid cells undergo meiosis to produce four haploid spores, which give rise to vegetative cells.