(a) State the reasons for which Hershey and Chase carried out their experiments.
(b) Answer the following questions based on the experiments of Hershey and Chase :
(i) Name the different radioactive isotopes they used, and explain how they used them.
(ii) Why did they need to agitate and spin their culture ?
(iii) Write their observations and the conclusions they arrived at.
a) To find out about what exactly is the transforming principle or the genetic material that is transferred down the hierarchy they performed this experiment.
1. S 32 and P35 were the radioactive isotopes used in their experiment.
2. The need to agitate and spin the culture was because they has to remove the viral coat once the contents were transferred.
3. Hershey and Chase concluded that DNA, not protein, was the genetic material. They determined that a protective protein coat was formed around the bacteriophage, but that the internal DNA is what conferred its ability to produce progeny inside a bacterium.