Bio 13 Lab Report

In the four-week long experiment conducted in the Bio 13 Lab, we were able to conduct a genetic analysis of the yeast S. cerevisiae, particularly investigating the inheritance and linkage of three genes: HIS4, LEU2, and LYS2. In week one, a suspension of spores was received and aliquots of the suspension were plates onto two YPD plates. After a week of yeast growth, haploid spore clones were carefully picked from the plates by sterile toothpicks and used to make patches on a new YPD plate, the master plate. In week three, the master plate was replicated onto three dropout plates: -His, -Leu, and -Lys. In the final week, the growth of the patches on the dropout plates were analyzed and class data was collected in order to conduct calculations for …show more content…
By the conclusion of the experiment, we determined which of three genes were linked and the distance between those linked genes. The first experiment involved in this four-week project was the plating of the suspension of spores and application of microscopy. This involved taking the suspension of spores that was already prepared by the Bio 13 staff and spreading the suspension onto two YPD plates by using sterile techniques. These sterile techniques included dipping the spreader used in plating into ethanol and then burning the ethanol off. The medium used in these plates was YPD-agar, which stands for Yeast Extract Peptone and Dextrose which is a complete, nutrient rich medium that has all the nutrients necessary for the growth of yeast, such as the S. cerevisiae used in this experiment. The most important component of this week’s experiment was the suspension of spores. Although not prepared by students, it is still critical to understand how it was