a1.2.3 - the sugar-phosphate 'backbone' of DNA/RNA

Question 1

define “backbone” as related to nucleic acid structure

Answer 1

the “backbone” is the alternating phosphate-sugar-phosphate-sugar-phosphate found in a polymer of nucleic acids. the relative strength of the backbone maintains the nucleotides in their specific sequence.

Question 2

explain how nucleotides can connect to form a nucleic acid polymer

Answer 2

• nucleotides connect by creating covalent bonds between the sugar of one nucleotide and the phosphate group of another nucleotide in a condensation reaction.
• the 5’ phosphate group on one nucleotide forms a new covalent bond with the 3’ carbon on the pentose of the next nucleotide. water is created as a biproduct.