What is not true about extinction? A. It is the end of existence of a species or group of related organisms
B. It is the end of existence of many species or group of unrelated organisms
C. Extinction occurs when the organism is no longer able to survive in changing conditions
D. About 99% of all species have become extinct

Explain why process 2 is so important to sexual reproduction identify processes 1 and 3 state one difference between the cells produced by process 1 and cells produced by process 3

Hedgerows have created a new ecosystem within britain’s a. farms b. cities c. forests d. industrial areas

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?