More Historical Perspective on DNA: From Gene to Protein

How did scientists discover the source of heritable genetic information?

Hershey-Chase Experiments (1952)
Even though the results of Griffith's transforming factor was DNA, other scientists still tested his idea.  
Watch the animation on the Hershey-Chase Experiment

1. What are the elements that make up a nucleic acid vs. a protein?
2. Why did Hershey and Chase use radioactive sulfer and phosphorus in their experiments?
3. Is DNA or protein the genetic material of a phage T2?
4. What evidence does this experiment give you to support this idea?

Let's review the structure of proteins.
Watch the video from education portal about the four levels of protein structure

Why might Rosalind Franklin's X-ray diffraction photograph have been interpreted as an alpha secondary structure?