Mmsc490 Exam 2 (A+ Graded)

During E. coli DNA replication, all newly synthesized or nascent DNA fragments must have one of the following characteristics a. a 5' hydroxyl and 3' triphosphate b. a 5' triphosphate and 3' monophosphate c. 5' monophosphate and 3' hydroxyl d. 5' triphosphate and 3' hydroxyl correct answers d. 5' triphosphate and 3' hydroxyl Among the 3 DNA polymerases in E. coli, DNA polymerases I and III differ in a number of properties that make DNA polymerase III a more suitable enzyme for chromosomal DNA synthesis. Which of the following is an important difference between the 2: a. DNA polymerase I does not require DNA template b. they require different sets of deoxynucleotides c. they differ in processivity d. DNA polymerase I is involved only in DNA repair correct answers c. they differ in processivity DNA replication requires the presence of a suitable template and a free 3'-OH end. this end may be generated by a. binding of terminal nucleotide-carrying protein to 3' end of the template b. Syntheses of an RNA primer at origin or at Okazaki fragment start points c. nicking of one strand of the duplex DNA followed by strand displacement d. Loop formation at the 3' end (self-priming) e. all of the above correct answers e. all of the above Although E. coli DNA polymerase I is not a chromosomal DNA replicase, it participates in DNA replication. What is its function? a. synthesizes Okazaki fragments b. replaces RNA primer with DNA