True or False: Strands of the backbone of DNA are parallel.

The strands of the backbone of DNA are actually anti-parallel. This means that while both strands run alongside each other, they orient in opposite directions. Each strand has a distinct directionality, defined by the orientation of its sugar-phosphate backbone. One strand runs from the 5' end to the 3' end, and the other runs from the 3' end to the 5' end. This anti-parallel structure is crucial for the complementary base pairing that occurs between the nucleotides of the two strands, allowing specific hydrogen bonding between adenine and thymine, and cytosine and guanine.

Understanding the anti-parallel nature of DNA strands is fundamental to grasping concepts like DNA replication and transcription, where enzymes and proteins recognize the orientation of the strands to function correctly. Therefore, stating that the strands are parallel is incorrect, making the answer false.