Used_in The definition of C++ [ c++.syntax.html ]. Used_in The definition of Java [ java.syntax.html ] Notation This uses my XBNF Extended BNF Notation where | indicates or, (...) indicates priority. For more information see [ intro_ebnf.html ].
To look at it in another way: Thymine(uracil in RNA) and cytosine are pyrimidines. Pyrimidines are single-ringed organic base that will only attach to purines, or adenine and guanine by hydrogen bond. Because cytosine and thymine are both pyrimidines, it cannot form a hydrogen bond with each other.
Adenine, Uracil, Cytosine and Guanine; (adenine bonds with uracil) and (cytosine bonds with guanine). Thymine DOES NOT appear in the sequence; for instance if the DNA stra â¦.8 people found this useful. Nucleotide Bases Nucleotide bases are heterocyclic atoms composed of nitrogen, a phosphate group, and a five-carbon sugar. 2  They play an important role in the structure of both DNA and RNA, heâ¦. 3  The Five Major Parts of the Brain At its most basic, the brain controls the body.