Building Blocks of DNA /RNA
(DeoxyriboNucleaic Acid and RiboNucleaic Acid)

The sugar part of DNA is deoxyribose which is very closely related to ribose which is itself similar to glucose. These three molecules are in the Moilin Library under bio_molecules.
You can use Moilin to examine
a-d-glucose

ribose and deoxy ribose

In DNA / RNA there are four bases Adenine, Guanine, Cytosine and Thymine


and these are also in the Moilin Library


DNA is a double stranded polymer with each strand composed of repeat units which contain -(phosphate-deoxyribose-base)-n with the phosphate and the deoxyribose in the polymer backbone.

The two strands in the structure of DNA are joined only by H-bonds between the bases. If P, S and one of A, G, C, T represent phosphate, sugar (deoxyribose) and base then the double helix may be represented as

The structure winds upon itself to form the double helix. The most important feature in the structure is that the H-bonding is very specific.  Adenine always H-bonds to Thymine (A....T) using two H-bonds and Cytosine always H-bonds to Guanine (C....G) using three H-bonds. These H-bonded base pairs have been modelled using Moilin and Mopac and they are in the Moilin Library. This is the Cytosine-Guanine pair.

Using Ortex and Pogl you can add dashed bonds for cosmetic purposes.

The phosphate-sugar-base repeat unit is called a nucleotide. Phosphate + ribose + adenine gives adenosine 5-phosphoric acid and this is also in the Library.

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