The two strands of the double helix are held together by base pairing in an antiparallel orientation, Which is a stereochemical(立体化学 E)consequence of the way that adenine and u thymine, and guanine and cytosine, pair with s each other. (Related to replication and transcription CHa sugarphosphate CHa Copyright o 2004 Pearson Education, Inc, publishing as Benjamin Cummings AThe two strands of the double helix are held together by base pairing in an antiparallel orientation, Which is a stereochemical (立体化学 的) consequence of the way that adenine and thymine, and guanine and cytosine, pair with each other. (Related to replication and transcription) DNA STRUCTURE ( ) 3