Beadle and Tatum (1940s) studies on Neurospora crassa experiment

Beadle and Tatum exposed Neurospora spores to radiation (x-ray, UV, or neutron) to make new mutations. The treated spores were used to start the sexual cycle in fruiting bodies. After any pair of cells and their nuclei undergo fusion, meiosis takes place almost immediately and results in eight sexual spores (ascospores) included in a single ascus. These are removed individually grew them individually in test tubes containing complete medium. Once each spore had established a growing colony, a small piece of the colony was transferred into another tube containing minimal medium.