Question

1. new dna is replicated in strands complementary to old dna because production of new dna follows the rules of ( base pairing / the double helix ) in a ( conservative / semi - conservative ) pattern.

Explanation:

1. For the first blank (base pairing / the double helix): DNA replication relies on the base - pairing rules (A - T, G - C in DNA) to synthesize complementary strands. The double helix is the structure of DNA, while base pairing is the rule that allows new strands to be made complementary to old ones. So the correct term here is "base pairing".
2. For the second blank (conservative / semi - conservative): In semi - conservative DNA replication, each new DNA molecule consists of one old (template) strand and one newly synthesized strand. Conservative replication would mean the original DNA molecule remains intact and a completely new one is made, which is not how DNA replicates. So the correct term here is "semi - conservative".

Answer:

First blank: base pairing
Second blank: semi - conservative