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Biology Lab Report Sample

Decent Essays

On Plate I (LB) and Plate II (LB + Ampicilin), E.coli growth was expected to occur. Since the environment was not selective in Plate I, growth was expected to be found as lawn. This prediction was confirmed by the experiment. On Plate II, it was expected that either lawn or colonies would be found. The observed growth occured as lawn. On Plate III (YPD) growth was predicted, given the presence of all the nutrients that the auxotrophic yeasts cannot synthetize. Due to the usual non-selectivity of the medium, lawn was the expected type of growth. However, growth actually manifested as red colonies, an occurrence which will be explained in the Discussion section. On Plate IV (YNB, -AA) and Plate V (YNB, -AA, +5% AS) no growth was expected to happen given the absence of amino acids, which the auxotrophic yeast could not synthetize. The results were as predicted. On Plate VI (YNB, +AA-Arg, -AS ), it was expected to obtain colonies, due to the selectivity of the environment. This indeed was observed, in the form of white colonies. …show more content…

This is consistent with the observed result. On Plate VIII (YNB, +AA+Arg, +AS, + 2% CAN), the GAP pathway was blocked by the presence of ammonium sulfate, and the CAN pathway was blocked by the presence of the canavanin toxin. Two possible outcomes were anticipated: either no growth, or selective growth (colonies) due to mutants developing resistance to canavanin. The latter situation was observed experimentally, with a few white colonies being

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