one of the salient features of the DNA double-helix structure is that the two polynucleotide chains have anti-parallel polarity . This means that if one chain has the polarity 5'→3', the other must have 3'→5' . This structural arrangement allows for proper base pairing via hydrogen bonds between the strands . While 'semiconservative' refers to the copying mechanism of DNA and 'discontinuous' refers to the synthesis of the lagging strand during replication, antiparallel specifically describes the physical orientation of the two chains . Mastering these fundamental structural concepts is a high-priority strategy, as NCERT textbooks serve as the definitive source for approximately 95% of NEET Biology questions .