DNA

• What is the main topic discussed in the study material?

  The evolution of DNA structure and its discovery
• What are the two important advances in biology mentioned?

  The 3-D structure of DNA and the discovery of nuclein
• Who discovered the 3-D structure of DNA and when?

  Watson and Crick in April 25, 1953
• Why was nuclein rejected by scientists initially?

  It was not recognized as the genetic material until later discoveries
• Who conducted the transformation experiment with Streptococcus pneumoniae?

  Frederick Griffith in 1928
• What did Griffith's transformation experiment demonstrate?

  It showed that a foreign substance could change a cell
• What type of virus did Hershey and Chase study?

  The T2 virus
• What was the significance of Chargaff's rules?

  They established that %T = %A and %G = %C in DNA
• What are the components of nucleic acids as described in the early 1950s?

  Phosphate, 5-C sugar, and four nitrogen bases
• Who were the key players in discovering the 3D structure of DNA?

  Watson, Crick, Wilkins, Franklin, and Pauling
• What did Watson and Crick propose about the structure of DNA?

  They proposed the double helix model with sugar-phosphate chains on the outside
• How did Watson and Crick utilize X-ray crystallography in their research?

  They used it to study the structure of DNA
• What was the breakthrough in Watson and Crick's model of DNA?

  They placed the sugar-phosphate backbone on the outside and nitrogen bases on the inside
• What is the term for the orientation of the two strands of DNA?

  Antiparallelism
• What prestigious award did Watson and Crick receive in 1962?

  The Nobel Prize
• What happened to Dr. Marie Maynard Daly in the context of DNA research?

  She influenced Watson's work but did not win a Nobel Prize
• What was Linus Pauling's proposal regarding DNA structure?

  He proposed a triple helix with bases facing outward
• What criticism did James Watson have regarding Linus Pauling's approach?

  Watson claimed Pauling did not read the literature or collaborate with others
• What was the hypothesis proposed by Watson and Crick regarding DNA replication?

  Each strand serves as a template for the other during replication
• What is the term for the model of DNA replication proposed by Watson and Crick?

  Semiconservative replication
• What are the steps involved in DNA replication according to Watson and Crick's model?

  • Each strand separates
  • Each strand serves as a template
  • Complementary bases are added
  • Exact copies are passed to daughter cells
• What activity is suggested for lab time with DNA?

  • Choose 5 random bases from bags
  • Make a complementary strand
• What was the predominant view of nuclein until the 1950s?

  It was not considered the genetic material
• What was the significance of the discoveries that indicated DNA as the genetic material?

  They shifted the scientific consensus towards recognizing DNA's role in heredity
• What was Erwin Chargaff's contribution to the study of DNA?

  He established the base pairing rules for DNA
• How did X-ray crystallography contribute to the understanding of DNA structure?

  It provided insights into the helical shape and dimensions of DNA
• What areas of study did Dr. Marie Maynard Daly focus on?

  Nucleic acid structure, protein synthesis, and histone chemistry