A hypochromic effect from pairing of purine and pyrimidine bases.
D000225:Adenine; D055598:Chemical Phenomena; D002621:Chemistry; D011687:Purines; D011743:Pyrimidines; D014498:Uracil
D011687:Purines; D011743:Pyrimidines; D014498:Uracil; D000225:Adenine