<span>Watson and Crick determined the base pairing by using the new information to construct a new double-stranded helix model with the nitrogen bases paired A to T and C to G in the center. This base pairing immediately suggested to Crick that one side of the molecule could serve as a template to exactly replicate DNA sequences to pass on genetic information during cell reproduction. This second, successful model was unveiled in February 1951.</span>
Mammal? Is this for science or?
Answer:D( Ribosomes
Explanation: Since most enzymes are proteins, it will be produced at the ribosomes. It may have an active and an inactive form. Which means another substance Will turn it on or off.
