Which of the following types of immunity do you expect would be the most effective in preventing a particular illness for a long period of time and why? (2 points)

active immunity: it allows the body to gain antibodies from several other outside sources.
active immunity: it allows development of memory cells that can later fight infection.
passive immunity: it requires less energy to be expended by the individual overall.
passive immunity: it does not require the body to be subjected to repeated vaccine injections.

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?

Grasses--> mice--> cats--> coyotes suppose 10,000 units of energy are available at the level of the grasses. what is the total number of energy units lost by the time energy reaches the coyote?

In what ways does the study of human population differ from the study of wildlife ecology