Deoxyribonucleic Acid

• is a biomolecule (nucleic acid).

  • ​monomers: nucleotides

  • elements: CHONP

• is genetic material that programs all cellular activity (blueprints).

• is found in the nucleus of the cell​.

• is double stranded with a helical structure.

Nucleotides

• are made of

  1. a phosphate group

  2. a pentose (5-carbon) sugar

     (DNA = deoxyrib​ose)

  3. nitrogenous base

     1. adenine

     2. guanine

     3. thymine

     4. cytosine

Chargaff's Rule

​The Base-Pairing Rule

• Adenine ALWAYS pairs with Thymine

  • 2 hydrogen bonds

• Guanine ALWAYS pairs with Cytosine

  • 3 hydrogen bonds​

DNA is Antiparallel.

Strands are oriented in opposite directions.

​5'

​3'

​3'

​5'

​3'

​5'

​5'

​3'

​5'

​5'

​3'

​3'