Structure of Nucleic Acids

Problem : What is the name of the sugar group in RNA? How is this different from the sugar group in DNA?

Problem : RNA does not contain the base group thymine. What base is found in its place? What is the structural difference between this base and thymine?

Problem : What is the main three-dimensional structural difference between DNA and RNA?

Problem : What prevents RNA from adopting the B helical form?

Problem : Why does Chargaff's rule not apply to RNA?