Final answer:
A mushroom produces sexual spores at the tip of club-shaped cells called basidia located on the gills, which then undergo meiosis to release haploid basidiospores into the environment.
Step-by-step explanation:
In the life cycle of the fungus Agaricus, a mushroom will produce a sexual spore at the tip of a club-shaped cell known as a basidium. The gills of a mushroom house these basidia where karyogamy takes place, leading to the formation of a diploid cell. This cell undergoes meiosis to yield haploid sexual spores, named basidiospores.
Though mushroom farmers generally employ an asexual reproduction method by using mycelium pieces, sexual reproduction is essential for the genetic diversity of the species. The basidia develop on the sides of the gills, extending from the fruiting body that emerges from a nutrient source, such as soil or tree trunks. Upon maturation, these spores are released into the environment to germinate and form new haploid hyphae.