If a strand of dna has the nitrogen base sequence 5'-atttgc-3', what will be the sequence of the matching strand? if a strand of dna has the nitrogen base sequence 5'-atttgc-3', what will be the sequence of the matching strand? 3'-atttgc-5' 3'-taaacg-5' 3'-uaaacg-5' 3'-tuuucg-5' 3'-gcaaat-5' submitrequest answer part b if a dna double helix is 100 nucleotide pairs long and contains 25 adenine bases, how many guanine bases does it contain? if a dna double helix is 100 nucleotide pairs long and contains 25 adenine bases, how many guanine bases does it contain? 200 150 25 50 75