Problem 1a
How were scientists able to determine that DNA, and not some other molecule, serves as the genetic material in bacteria and bacteriophages?
Problem 1b
How was it determined that the structure of DNA is a double helix with the two strands held together by hydrogen bonds formed between complementary nitrogenous bases?
Problem 1c
How do we know that G pairs with C and that A pairs with T as complementary base pairs are formed?
Problem 2
Most center around DNA and RNA and their role of serving as the genetic material. Write a short essay that contrasts these molecules, including a comparison of advantages conferred by their structure that each of them has over the other in serving in this role.
Problem 3
Discuss the reasons proteins were generally favored over DNA as the genetic material before 1940. What was the role of the tetranucleotide hypothesis in this controversy?
Problem 4
Contrast the contributions made to an understanding of transformation by Griffith and by Avery and his colleagues.
Problem 5
When Avery and his colleagues had obtained what was concluded to be the transforming factor from the IIIS virulent cells, they treated the fraction with proteases, RNase, and DNase, followed in each case by the assay for retention or loss of transforming ability. What were the purpose and results of these experiments? What conclusions were drawn?
Problem 6
Why were ³²P and ³⁵S chosen for use in the Hershey–Chase experiment? Discuss the rationale and conclusions of this experiment.
Ch. 9 - DNA Structure and Analysis