In 3–5 sentences, compare and contrast the flow of matter and energy in each trophic level for land-based ecosystems and marine ecosystems. How and why

are they similar, and how and why are they different? (4 points)

The body is protected against harmful flu viruses by

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?

Mineral rich water heated by newly found oceanic crust escapes through cracks in the ocean floor called