1. The problem statement, all variables and given/known data Which of the following are true statements ? a) DNA is composed of a series of necleotides, each of which is made up of a phosphoric acid unit, a sugar unit and a cyclic nitrogen base. b) In DNA the base must be either alanine, threonine, glutamine, or cysteine. c) In the three-dimensional Watson-Crick structure of DNA, two polynucleotide DNA strands wind around each other to form a double helix. d) The DNA sequence of base pairs in the nucleus of a cell represents the genetic code that controls inherited characteristics. e) Genes are the sequence of bases in DNA that are the code for the synthesis of a single protein within the body. 2. The attempt at a solution NOT SURE BUT : a) [FALSE]It can not be a because it should be phosphate group instead of cyclic nitrogen base b) [TRUE?] I thought it should be correct, since DNA bases are adenine (A), guanine (G), thymine (T), and cytosine (C) c) [TRUE] It's true that the two polynucleotide chains in DNA molecule. d) [TRUE] the bases are unique, that tells the characteristics e) [FALSE?] I'm not sure, but I thought that it should be since genes are code for synthesis of proteins. I tried bcde and bcd but it's incorrect. :( Please help, thank you!