How did knowledge of dna's structure scientists understand dna replication?

DNA's structure is a double helix.  This explained DNA replication because it helped get a better understanding of the nucleotides.  In order for DNA to stick to one another, the bases need to complementary.  

DNA carries all of the information for your physical characteristics, which are essentially determined by proteins. So, DNA contains the instructions for making a protein. In DNA, each protein is encoded by a gene (a specific sequence of DNA nucleotides that specify how a single protein is to be made).

Explanation:

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