What are 4 human activities that interfere with ecosystems, food chains and food webs.

Microorganisms are involved in each of the following processes excepta. smog production.b. food production.c. infection.d. o2 production.e. decomposition of organic material.

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?

If a strand of dna has 35% thymine. what is the percentage of cytosine, adenine, guanine?