Question 2 (b) Explain why DNA replication cannot proceed to the regions of the chromosome labeled as I in Figure 1B unless topoisomerase binds ahead of each advancing replication fork in region II .

The similarities of organisms in which two areas numbered above provide the best evidence for common ancestry between organisms in both locations?

Why did adult crab numbers decline in he ecosystem, even though sea stars were still available?

Which of the following is likely not involved in this example of ecological succession? a) the rotting remains of plants add to the fertility of the soil. b)the soil becomes so fertile that eel grass is replaced by other plant species. c) the roots from plants stabilize the sediment, keeping it in place. d) the concentration of salt becomes so high that all plant life is destroyed.