Under high-powered microscope dan sees a cellar organelle

How did the miller-urey experiment impact the way scientists think about the origins of life? use what you know about the miller-urey experiments to discuss the factors needed for life to arise, and speculate on whether life could arise on another planet.

Which excerpt from the land, part 4 best supports the claim that paul is a talented horseback rider? a/“figure that says more than anything else! now, i want to ride that stallion! " b/my daddy shook his head. "paul only rides horses he knows. ” c/? i glanced over at the other rider. the fellow was older than i, and had the weight of a man on him. d/a man out of alabama, man name of ray sutcliffe, told my daddy i was such a good rider, he wanted me to ride some races for him.

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?