If cells are grown in a medium containing radioactive 15n, which of these molecules will be labeled?

The molecules that will be labeled will be both proteins and nuclei acids. This is  because both proteins and amino acids contain nitrogen. Proteins are large, complex molecules that play many critical roles in the body. They perform many of work in cells and are required for the structure, function, and regulation of the body's organs and tissues. Amino acids are the building blocks of proteins and are made amine groups which contain radioactive nitrogen, while nucleic acids contain nitrogenous bases with radioactive nitrogen. 

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