In the laboratory, students can actively explore concepts and experience the nature of scientific research. We have devised a 5-wk laboratory project in our introductory college biology course whose aim was to improve understanding in five major concepts that are central to basic cellular, molecular biology, and genetics while teaching molecular biology techniques. The project was focused on the production of adenine in Saccharomyces cerevisiae and investigated the nature of mutant red colonies of this yeast. Students created red mutants from a wild-type strain, amplified the two genes capable of giving rise to the red phenotype, and then analyzed the nucleotide sequences. A quiz assessing student understanding in the five areas was given at the start and the end of the course. Analysis of the quiz showed significant improvement in each of the areas. These areas were taught in the laboratory and the classroom; therefore, students were surveyed to determine whether the laboratory played a role in their improved understanding of the five areas. Student survey data demonstrated that the laboratory did have an important role in their learning of the concepts. This project simulated steps in a research project and could be adapted for an advanced course in genetics.