The document introduces the budding yeast Saccharomyces cerevisiae as a model organism for genetics studies, describing its life cycle between haploid and diploid forms and advantages like its small genome and rapid growth. Methods for conducting genetic screens in yeast are discussed, including how early work isolating cell cycle genes used temperature-sensitive mutants and screening for cell cycle arrest. Meiosis and sporulation in yeast allows studying meiotic divisions and genetic analysis by ensuring mutations are present in only one gene.