AP BIOLOGY

Detailed explanation-1: -In their experiments, Hershey and Chase showed that when bacteriophages, which are composed of DNA and protein, infect bacteria, their DNA enters the host bacterial cell, but most of their protein does not. Hershey and Chase and subsequent discoveries all served to prove that DNA is the hereditary material.

Detailed explanation-2: -Alfred Hershey and Martha Chase showed that only the DNA of a virus needs to enter a bacterium to infect it. Their experiment provided strong support for the idea that genes are made of DNA.

Detailed explanation-3: -Hershey and Chase experiment proving DNA as the genetic material was based on the principle Transduction which is the process by which DNA is transferred from one bacterium to another by a virus.

Detailed explanation-4: -Since the protein coat was lighter, it was found in the supernatant while the infected bacteria got settled at the bottom of the centrifuge tube. Hence, it was proved that DNA is the genetic material as it was transferred from virus to bacteria.

Detailed explanation-5: -Hershey and Chase used radioactivity to answer the question of whether protein or DNA was the genetic material. They labeled the DNA in a T2 phage with radioactive phosphate, and labeled the protein coat of the T2 phage with radioactive sulfur.