D.N.A is a polynucleotide - it's made up of lots of nucleotides joined together.
- Each nucleotide is made up from a pentose sugar, a phosphate group and a nitrogenous base.
- The sugar in D.N.A is a deoxyribose sugar.
- Each nucleotide has the same sugar and phosphate, however the base on each nucleotide varies.
- There are 4 bases: adenine....thymine....cytosine....guanine.
Two polynucleotide strands join together to form a double-helix.
- The nucleotides join up between the phosphate group of one nucleotide and the sugar of another, creating a sugar-phosphate backbone.
- Two D.N.A polynucleotide strands are joined by hydrogen bonds between corresponding bases. A and T. C and G.
The Structure of D.N.A.
- D.N.A molecules are long and are coiled up very tightly, so a lot of genetic information…