Worksheet 2 on DNA replication Concept 2: DNA replication is bi-directional (in vivo). What is the experimental design and result? What is the advantage of a bi-directional replication to a uni-directional replication? Concept 3: DNA replication has a leading and a lagging strand (in vivo). What is the experimental design and result? Why are there lagging strands? Let’s draw a DNA replication diagram.1. Examine the figure below. Where are the leading strands in the last replication bubble? A. Top left strand and top right strand B. Top right strand and bottom right strand C. Bottom right strand and top left strand D. Bottom left strand and top right strand 2. What will occur after the event depicted in the last replication bubble? A. DNA primase places RNA primers B. DNA polymerase I fills in the gap. C. DNA polymerase I removes RNA primers. D. DNA ligase connects adjacent strands through phosphodiester bonds. 3. A student tries to repeat an in vitro DNA replication reaction using E.coli DNA polymerase III. When DNA polymerase III was isolated from E.coli, it lost part of its enzymatic activities. Discuss with your group what will happen to DNA replication if any of the following enzymatic activities is lost. Specify which step is affected. 5’ to 3’ polymerase activity ______________________________ 5’ to 3’ exonuclease activity ______________________________ 3’ to 5’ exonuclease activity ______________________________ Beta unit function