Cataracts Facts. 1  Cataracts are changes in clarity of the natural lens inside the eye that gradually degrade visual quality. The natural lens sits behind the colored part of the eye (iris) in the area of the pupil, and cannot be directly seen with the naked eye unless it becomes extremely cloudy.
Hershey and Chase. Alfred Hershey and Martha Chase did an Experiment in 1952 that was called the Hershey-Chase Experiment. This experiment set out to determine what composed the genetic material of a bacteriophage. A bacteriophage is a virus that infects a bacterium.
These bacteria were lysed to release phage progeny. The progeny of the phages that were originally labeled with 32 P remained labeled, while the progeny of the phages originally labeled with 35 S were unlabeled. Thus, the HersheyâChase experiment helped confirm that DNA, not protein, is the genetic material.Hershey and Chase showed that the introduction of deoxyribonuclease (referred to as DNase), an enzyme that breaks down DNA, into a solution containing the labeled bacteriophages did not introduce any 32 P into the solution.he results of the AveryâMacLeodâMcCarty experiment, published in 1944, suggested that DNA was the genetic material, but there was still some hesitation within the general scientific community to accept this, which set the stage for the HersheyâChase experiment.