The adenine bases in a DNA molecule are radioactively labeled.The DNA is then placed in a solution containing unlabeled nucleotides and the enzymes needed for DNA replication.The DNA molecule is allowed to replicate twice,forming four new DNA molecules.The radioactively labeled adenine would be found in

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During DNA replication, the new strands are synthesized in a semi-conservative manner where each new strand contains one original (parental) strand and one newly synthesized strand. Therefore, in the first round of replication, two new DNA molecules are formed, each containing one original strand labeled with radioactive adenine and one newly synthesized strand without the label. In the second round of replication, these two new DNA molecules serve as templates for the synthesis of two additional DNA molecules, resulting in a total of four DNA molecules. However, only two of these four DNA molecules would contain the original labeled adenine bases. Thus, the radioactively labeled adenine would be found in two of the eight strands.

The Adenine Bases in a DNA Molecule Are Radioactively Labeled