Question

The authors' main purpose of including the information about X-ray evidence and density is to

• A. Establish that DNA is the molecule that carries the genetic information
• B. Present an alternate hypothesis about the composition of a nucleotide
• C. Provide support for the authors' claim about the number of chains in a molecule of DNA
• D. Confirm the relationship between the density of DNA and the known chemical formula of DNA

Answer 1

The correct option is C Provide support for the authors' claim about the number of chains in a molecule of DNA

The data from the X-ray density studies have been included to prove that DNA is formed not of one chain (as had been assumed from its chemical structure) but of two chains that are coiled around a common fibre axis. So, the correct option is 'Provide support for the authors' claim about the number of chains in a molecule of DNA'.