Which of the following applies to the Kirby-Bauer test? Select all that apply. 1. This test determines if an antibacterial drug is bacteriostatic or bactericidal.

2. Bacteria that have a zone of inhibition are considered susceptible to the tested drug.

3. Bacteria that lack a zone of inhibition are resistant to the tested drug.

4. This test determines if a bacterium is resistant to a specific antibacterial drug.

5. This test reveals if a bacterium is a pathogen.

Keeping in mind the life cycle of bacteriophages, consider the following problem: during the reproductive cycle of a temperate bacteriophage, the viral dna inserts into the bacterial chromosome where the resultant prophage behaves much like a trojan horse. it can remain quiescent, or it can become lytic and initiate a burst of progeny viruses. several operons maintain the prophage state by interacting with a repressor that keeps the lytic cycle in check. insults (ultraviolet light, for example) to the bacterial cell lead to a partial breakdown of the repressor, which in turn causes the production of enzymes involved in the lytic cycle. as stated in this simple form, would you consider this system of regulation to be operating under positive or negative control?

What enzyme is most important for dna replication and why?

What are two ways that harvesting algae from the ocean may benefit human society? how might the harvest of algae negatively impact the ocean communities where that algae grows? how could this be prevented?