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Meselson and Stahl Experiment

APBIO-4JDLNB

In the landmark Meselson and Stahl experiment, E. coli bacteria were grown for several generations in media containing nitrogen-15. Later, they transferred the E. coli to media containing nitrogen-14.

They analyzed the DNA after separating the DNA by mass using a centrifuge. The results that they found were shown in the diagram below.

Villarreal, Mariana Ruiz. Meselson-stahl Experiment. Digital image. Wikimedia Commons. N.p., 17 Sept. 2008. Web.

Which of the following was illustrated in the experiment by Meselson and Stahl?

A

DNA exhibits a double helix structure.

B

DNA was the molecule of heredity.

C

DNA copies itself such that each strand is half old and half newly constructed.

D

Amino acids may have been the first biological molecules formed on Earth.