The Effects of Salt and Caffeine on Dictyostelium discoideum
By: Alyssa Marrero
Group members: Megan and Tyler
Introduction:
In our experiment, we tested the effects of salt and caffeine on the slime mold Dictyostelium discoideum. Dictyostelium discoideum is a cellular slime mold, which lives in warm and moist environments. It spends most its life cycle as feeding myxamoebae consuming bacteria on the forest floor. When Dictyostelium discoideum runs out of food, the myxamoebae aggregate and form a migratory pseudoplasmodium (or slug), which searches for a new environment in order to find food. When the slug finds its new environment it settles on its posterior end, forming the shape of a Mexican hat. The Mexican hat formation then culminates …show more content…
We had one Petri dish that was our control, which was streaked with E.coli and was kept at normal room temperature and normal lighting. The second Petri dish was also streaked with E.coli and kept at room temperature and normal lighting, but six piles of salt were added to the Petri dish. The third Petri dish was also kept at room temperature and normal lighting, but a thin layer of coffee (contains caffeine) was added to the plate. In order to avoid contamination of our experiments, we used a loop that was placed in a flame to sterilize it before using it to place E.coli on the plates and we wore gloves during the procedures. Times we observed the experiments: 5pm on the day of our experiment, the day after our experiment and 4 days after the experiment.
Results:
When we observed the experiments at 5pm the day of our experiment and the day after our experiment there was no results in any of our plates, so we decided to check again in three days to give our experiments more time. When the three days were over we checked the experiments and had results. For our control we had a lot of fruiting bodies and a few slugs. For the salt experiment there were only a few fruiting bodies, which all were far away from the salt piles. The caffeine experiment had a lot of fruiting bodies and slugs on the plate (a lot more than the control plate).