Two cells grow over a period of time, and their dimensions are measured under a microscope. Their surface areas and volumes are calculated and shown in the table below. Which of the following explains which cell will exchange materials with its environment more slowly? Cell A Cell B
Initial Surface Area (in square units) 10 10
Initial Volume (in cubic units) 2 2
Final Surface Area (in square units) 15 28
Final Volume (in cubic units) 4.5 10
Cell A, since it now has a greater surface-area-to-volume ratio than Cell B
Cell A, since it now has a smaller surface-area-to-volume ratio than Cell B
Cell B, since it now has a greater surface-area-to-volume ratio than Cell A
Cell B, since it now has a smaller surface-area-to-volume ratio than Cell A

You can tell from this karyotype that the individual is female because the karyotype has two chromosomes labeled

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?

Which is the correct order in the scientific process? ask a question ® form a hypothesis ® make an observation ask a question ® make an observation ® form a hypothesis make an observation ® form a hypothesis ® ask a question make an observation ® ask a question ® form a hypothesis