Some scientists believe that many years ago, most life on earth lived in water. over time, some fish grew small legs and lungs that allowed them to come onto land. these fish most likely did this because they a) needed to find shelter. b) were exploring new habitats. c) were trying to escape disease. eliminate d) were in search of food to eat.

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 materials must dams have to produce electricity, and what must occur?

Interactions between organisms and their environment impact the organism’s overall population. the jaguar panthera onca is the largest cat in north america. it is found in areas across the southwest, including arizona, new mexico, and texas. it is a carnivore that has powerful jaws and sharp teeth and preys on fish, turtles, tapirs, and many smaller mammals. which shows the relationship between the jaguar and turtles?