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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?

Following from the previous question about the single-celled microorganism, if each cell does not have a nucleus, you could conclude it could be a ______.

You have a culture of E. coli growing in log phase in a chemically defined medium containing glucose as the sole source of carbon. You take a small sample of cells and transfer them to another chemically defined medium that contains lactose as the sole source of carbon. In this new environment, you would predict these cells would first enter what phase of growth?

Microbiologists estimate we have grown and studied less than 1% of all prokaryotes present on Earth. We have been estimating this same number for at least the past two decades. What is the most likely explanation for why this number has stayed relatively constant at 1%?