Use the Figure to Answer the Following Question

question 25

Multiple Choice

Use the figure to answer the following question. In the late 1950s, Meselson and Stahl grew bacteria in a medium containing "heavy" (radioactive) nitrogen (15N) and then transferred them to a medium containing 14N (non-radioactive) . Which of the results in the figure would be expected after one round of DNA replication in the presence of 14N?

• A) A
• B) B
• C) C
• D) D

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