The Hershey-Chase experiment is best known for demonstrating that which molecule is the genetic material?

The Hershey-Chase experiment is best known for demonstrating that which molecule is the genetic material?

• A. DNA
• B. RNA
• C. Protein
• D. Carbohydrates

Answer: (A)

Understanding what carries genetic information is being tested here. The Hershey-Chase experiment showed that DNA is the molecule that stores and passes on genetic instructions, at least for the virus system they studied. They labeled the phage DNA with radioactive phosphorus and the phage protein with radioactive sulfur. After allowing infection and then separating the viral coats from the bacterial cells, only the phosphorus signal showed up inside the cells and in the newly produced phages, while the sulfur signal did not. This indicates that the genetic material entering the bacteria and directing the production of progeny phages was DNA, not protein. RNA isn’t demonstrated by this experiment, and carbohydrates aren’t used to carry genetic information, so DNA is the molecule identified as the genetic material in this classic study.

Understanding what carries genetic information is being tested here. The Hershey-Chase experiment showed that DNA is the molecule that stores and passes on genetic instructions, at least for the virus system they studied. They labeled the phage DNA with radioactive phosphorus and the phage protein with radioactive sulfur. After allowing infection and then separating the viral coats from the bacterial cells, only the phosphorus signal showed up inside the cells and in the newly produced phages, while the sulfur signal did not. This indicates that the genetic material entering the bacteria and directing the production of progeny phages was DNA, not protein. RNA isn’t demonstrated by this experiment, and carbohydrates aren’t used to carry genetic information, so DNA is the molecule identified as the genetic material in this classic study.