Heterocyclic amines are sometimes called nitrogen bases
or simply bases. The heterocyclic amines are derived from
two root structures: purines or pyrimidines. The purine root
has both a six and a five member ring; the pyrimidine has a single
six member ring.
There are two major purines, adenine (A) and guanine (G),
and three major pyrimidines, cytosine (C), uracil (U), and thymine
(T). The structures are shown in the graphic on the left. As
you can see, these structures are called "bases" because
the amine groups as part of the ring or as a side chain have
a basic property in water.
A major difference between DNA and RNA is that DNA contains
thymine, but not uracil, while RNA contains uracil but not thymine.
The other three heterocyclic amines, adenine, guanine, and cytosine
are found in both DNA and RNA. For convenience, you may remember,
the list of heterocyclic amines in DNA by the words: The Amazing
Gene Code (TAGC).
Heterocylic Amines - Chime
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|Quiz: Write out the full name
of the heterocyclic amines given by: