The Salinity experiment teaches students skills of a scientist, some of which are: thinking of a question to test, the controlled, manipulated, and responding variables as well as a hypothesis and prediction, and using basic lab equipment. What students test for is which molarity of growth media works the best to grow Halobacterium (NRC-1) and to do this they start by inoculating 3 of 4 flasks of growth media (1 for control) with Halobacterium, labeling them, and leaving them to stir on the stir plate for 48 hours. What we did was conducted a more extensive version of the same experiment and for a different reason; most teachers only have access to basic lab equipment like stir plates when an incubator/agitator would be ideal, so it was our job to find out how long Halobacterium takes to double in each of the 5 given growth medium solutions (different molarities of salt; 2.3, 2.8, 3.3, 3.8, and 4.3) using stir plates, this helps teachers plan classes more efficiently. We set up the experiment for each molarity with flasks labeled control, 1, 2, and 3, and had them all running at once and took the optical density (OD) every so often for control and 1, 2, then 3. We ran this experiment 4 times for accuracy but unfortunately we kept running into problems and the data we got seemed rather inconclusive.
Dunaliella salina vs. Iodine
Earlier studies indicate that Dunaliella tertiolecta produces Thryoxine, which benefitted creatures that fed on it such as sea urchins. We sought to find whether Dunaliella salina also produced Thyroxine. We failed to find any results in our first trial but the results of our second trial indicated D. salina may produce Thyroxine if subjected to intense continuous light.
Dunaliella salina vs. Halobacterium salinarum
Prior observations suggested that Dunaliella salina and Halobacterium salinarum may have a symbiotic relationship. We hypothesized that D. salina provided amino acids for H. salinarum. We compared growth rates and end results between different cultures containing either D. salina, H. salinarum, or both, with and without amino acids. Our experiments suggest that D. salina benefits from the presence of H. salinarum but H. salinarum gains little from D. salina.
Artemia salina vs Iodine
We set out to test whether Artemia salina were affected by Iodine as a control experiment for testing if they were affected by the growth hormone Thyroxine. While we collected data suggesting that too much Iodine would be fatal and less than that would probably not affect the Brine Shrimp, our experiment was riddled with error. We decided not to redo the experiment as our reason for this experiment was to act as a control for a later experiment. The later experiment depended on Dunaliella Salina producing Thyroxine, but we did not find any Thyroxine produced.
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