2.2 Nucleic Acids

Question 1

Name the groups present in a DNA/RNA nucleotide

Answer 1

pentose sugar (ribose in RNA, deoxyribose in DNA), phosphate
- nitrogenous bases - pyrimidines (cytosine, thymine/uracil) and purines (guanine, adenine)
- glycosidic bond between base and sugar, phosphodiester bond between sugar and phosphate

Question 2

Describe how DNA mononucleotides join together to form a DNA polymer/strand​

Answer 2

• 3 hydrogen bonds between C and G, 2 hydrogen bonds between A and T
• strands connect antiparallel
• phosphodiester bonds between nucleotides

Question 3

Compare and contrast the structure of a DNA and RNA strand

Answer 3

Similarities:
- pentose sugar
- sugar phosphate backbone
- cytosine, guanine, adenine
Differences:
DNA - deoxyribose, double-stranded, thymine
RNA - ribose, single-stranded, uracil