From a modern genetic perspective, this is defined as evolution.
Adenine (A) binds with Thymine (T).
<span>Guanine (G) binds with Cytosine (C).
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Adenine and Guanine are purines. Thymine and Cytosine are pyrimidines.
Hope this helps !
Photon
Base pairing between the DNA template strand and the RNA nucleotides
