91Ó°ÊÓ

Which of the following statements about DNA polymerases is NOT accurate? a. They are enzymes. b. They make DNA polymers by adding nucleotides to the \(3^{\prime}\) end of a growing chain. c. They require ATP for addition of each nucleotide to a growing strand. d. They require a single-stranded template.

. Which of the following is an accurate distinction between DNA polymerases in \(E\). coli? a. DNA Pol I synthesizes the leading strand, and DNA Pol III synthesizes the lagging strand. b. DNA Pol III synthesizes the leading strand, and DNA Pol I synthesizes Okazaki fragments. c. DNA Pol III requires a free \(3^{\prime}\) OH to add a nucleotide to a growing strand; DNA Pol I does not. d. DNA Pol I and DNA Pol III play a role in DNA replication; DNA Pol II is involved in DNA repair.

Chargaff studied the composition of DNA from different sources and found that a. the number of phosphate groups always equals the number of 5 -carbon sugars. b. the proportion of A equals that of \(\mathrm{C}\) and the proportion of \(\mathrm{G}\) equals that of \(\mathrm{T}\) c. the proportion of A equals that of \(\mathrm{T}\) and the proportion of \(\mathrm{G}\) equals that of \(\mathrm{C}\). d. purines bind to pyrimidines.

Which of the following is NOT part of the Watson-Crick model of the structure of DNA? a. DNA is composed of two strands. b. The two DNA strands are oriented in parallel \(\left(5^{\prime}-\right.\) to- \(\left.3^{\prime}\right)\). c. Purines bind to pyrimidines. d. DNA forms a double helix.