Topic 2.6:  Structure of DNA and RNA

Essential Idea:  The structure of DNA allows efficient storage of genetic information.
At SHS, Topic 2.6 is taught in the following class unit(s):

Statements & Objectives:

2.6.U1  The nucleic acids DNA and RNA are polymers of nucleotides.
  • State the two types of nucleic acid.
  • Outline the parts of a nucleotide.
  • Identify and label carbons by number (for example, C1, C2, C3) on a nucleotide drawing.
  • Explain how nucleotides can connect to form a nucleic acid polymer.
  • State the names of the nitrogenous bases found in DNA and RNA.
  • Identify nitrogenous bases as either a pyrimidine or purine.
  • State the complementary base pairing rules.
2.6.U2  DNA differs from RNA in the number of strands present, the base composition and the type of pentose.
  • Compare the structure of DNA and RNA.
2.6.U3  DNA is double helix made of two antiparallel strands of nucleotides linked by hydrogen bonding between complimentary base pairs.
  • Define antiparallel in relation to DNA structure.
  • Outline the formation of a DNA double helix by hydrogen bonding between nitrogenous bases.
  • Identify the four bases of DNA based on the numbers of rings (purines or pyrimidines) and the number of hydrogen bonds it can form.
  • State the number of nitrogenous bases per complete turn of the DNA double helix.
2.6.A1  Crick and Watson’s elucidation of the structure of DNA using model making.
  • Outline the role of Chargaff, Watson, Crick, Franklin and Wilkins in the discovery of DNA structure.
  • Explain how Watson and Crick used model building to determine the structure of DNA. 
2.6.S1  Drawing simple diagrams of the structure of single nucleotides of DNA and RNA, using circles, pentagons, and rectangles to represent phosphates, pentoses and bases.
  • Draw the basic structure of a single nucleotide (using circle, pentagon and rectangle).
  • Draw a simple diagram of the structure of RNA.
  • Draw a simple diagram of the structure of DNA,
  • Identify and label the 5’ and 3’ ends on a DNA or RNA diagram
2.6.NOS  Using models as representation of the real world- Crick and Watson used model making to discover the structure of DNA.
  • List types of models used in science.
  • State a common feature of models in science.
  • List ways in which models are different from the structure or process it represents.
"When we try to pick out anything by itself, we find it hitched to everything else in the Universe."  -  John Muir,   1911