The protects the cell from drying and provides resistance to chemicals and invasion by viruses.

Use the drop-down menu to complete the statement. an electron in the first energy level of the electron cloud has an electron in the third energy level.a. a lower energy thanb. a higher energy thanc. the same energy as

What are some possible short and long term medical concerns for crew members on longer space exploration trips

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?