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You find multicellular, eukaryotic, heterotrophic organisms living as part of the normal human microbiota. These organisms are most likely ______.

You take a scraping of some of your epithelial skin cells and isolate your mitochondrial DNA. Upon sequencing this mitochondrial DNA, you find it is _______.

Optional up to 2 points of extra credit: Here we see an estimation of daily infections by SARS-CoV-2 based on wastewater data collected during the COVID pandemic, tracking the repeated waves of infection we have experienced in the U.S. 1. How is it that we are able to measure SARS-CoV-2 in wastewater, i.e., what does this tell us about infections with this virus? What is it that we are measuring in this wastewater? 2. Make a prediction based on this graph and your understanding of the ongoing COVID pandemic. Where do you think cases will go in the future? Explain your thinking – why do you think cases will behave as you predict, and what variables will contribute to that trend.

You leave two open Petri dishes out overnight in the lab: one containing a complex medium like tryptic soy agar (TSA), and the other a chemically defined medium like glucose salts agar (GSA). On which do you expect more growth the next day, and why? Please briefly explain, and be sure to compare and contrast these two types of media as part of your answer.

You are considering treating an infection of Staphylococcus aureus with penicillin. During which growth phase will S. aureus be most susceptible (sensitive) to penicillin?

The theory of spontaneous generation, disproven by the work of researchers such as Louis Pasteur, stated that living organisms could ______.

You sample some surfaces using a sterile cotton swab moistened with sterile water, and streak the swab onto the surface of two different types of media: one Petri dish containing the complex medium tryptic soy agar (TSA), and the other the chemically defined medium glucose salts agar (GSA). Following incubation, on which Petri dish do you expect more growth, and why? Please briefly explain, and be sure to compare and contrast these two types of media as part of your answer.

You take two images of a single eukaryotic cell using a light microscope at 1,000x magnification and an electron microscope at 1,000x magnification. Compared to the light microscope, the image in the electron microscope should be ______.

You are working to characterize a new species of bacteria you have discovered! You Gram stain some cells and observe them as pink rods. If you performed your stain correctly, this observation most accurately confirms ______.

You treat the following five cultures of bacteria with penicillin: Bacillus subtilis, E. coli, Mycobacterium tuberculosis, Mycoplasma genitalium, and Staphylococcus aureus. Assume all are “wild type” and have not acquired specific resistance to penicillin (i.e., resistance has not been selected for in any of these strains). Which of these is most likely to survive your treatment with the least harm, i.e., is the most intrinsically resistant to this treatment of penicillin?