Can occur when the body loses too much water content and essential body salts.

Astudent observes a star from two positions of earth in its orbit, in summer and winter, and measures the change in the position of the star. which of these can be best calculated by this method?

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 function does the limb sever in each animal? how are the limb bones of the four animals similar? based on these similarities what can be inferred about the evolution of the four animals.