which of the following characteristics allowed hershey and chase to determine whether the genetic material was made of dna or protein?
Which of the following characteristics allowed Hershey and Chase to determine whether the genetic material was made of DNA or protein?
Hershey and Chase conducted an experiment using bacteriophages, which are viruses that infect bacteria. They wanted to determine whether the genetic material of bacteriophages was made of DNA or protein.
In their experiment, they labeled the DNA of the bacteriophage with radioactive phosphorus (32P) and labeled the protein coat of the bacteriophage with radioactive sulfur (35S). They then infected bacterial cells with these labeled bacteriophages.
After the infection, Hershey and Chase used a blender to separate the bacteriophage particles from the bacterial cells. They then spun the mixture in a centrifuge to separate the heavier bacterial cells from the lighter phage particles.
The key characteristic that allowed Hershey and Chase to determine whether the genetic material was made of DNA or protein was the presence of radioactive phosphorus (32P) in the bacterial cells. They observed that the radioactive phosphorus, representing the DNA, was found inside the bacterial cells after infection, while the radioactive sulfur (35S), representing the protein coat, remained outside the cells.
This result led to the conclusion that DNA, not protein, was the genetic material being transferred to the bacterial cells during infection. The presence of radioactive phosphorus in the bacterial cells confirmed that DNA was the molecule responsible for transmitting the genetic information. Therefore, the characteristic of radioactive phosphorus allowed Hershey and Chase to determine that the genetic material was made of DNA, not protein.