nucleic acids

nucleic acids

• organic molecules that code for everything in a cell

• comprised of C, H, O, N, and P

• nucleotides: monomers of nucleic acids

  • comprised of a phosphate group, a sugar group (5-C pentose), and a nitrogenous base

    • phosphate contributes to overall negative charge

  • nitrogenous base linked to C’1

  • phosphate group linked to 5’C

• includes DNA and RNA

• read 5’-3’

nucleic acid sugars

• deoxyribose: found in DNA

  • only one OH

• ribose: found in RNA

  • contains two OH groups

nitrogenous bases

• store genetic information and hold the structure of DNA

• polymerization occurs through a covalent phosphodiester bond

  • bond between 5’C phosphate on one nucleotide and on 3’C OH on another

• pyrimidines: one “circle”

  • cytosine, uracil, thymine (CUT the PY)

• purines: two “circles”

  • guanine, adenine

• hydrogen bonds between bases

DNA

• deoxyribonucleic acid

• contains T (thymine), along with C, G, A

  • A-T

  • C-G

• stores genetic information

• double helix structure with an alternating sugar and phosphate backbone

  • strands run antiparallel of each other

RNA

• helps encode for proteins

• single helix structure

• contains U (uracil) in place of T

  • U-A

• has a primary and secondary structure

  • secondary RNA structure results from complementary base pairing between sequences on the same RNA strand