5/5/11
Scavenger Hunt
What is genetic material composed of?
DNA is a relatively simple molecule, composed of only 4 different subunits. For
this reason, many early scientists did not consider DNA to be complex enough
to be genetic material.
What experiments helped identify the role of DNA?
Griffith’s Discovery of Transformation: In 1928, Frederick Griffith was
working with two related strains of bacteria. The S strain causes
pneumonia and is covered by a capsule of polysaccharides.
Avery’s Experiments with Nucleic Acids: In 1940s, Oswald Avery wanted to
determine whether the transforming agent in Griffith’s experiments was
protein, RNA, or DNA.
Hershey-Chase Experiment: Hershey and Chase studied bacteriophages, viruses
that infect bacterial cells and cause the cells to produce viruses.
Bacteriophages are made of proteins and DNA.
What is the shape of a DNA molecule?
A DNA molecule is shaped like a spiral staircase and is composed of two
parallel strands of linked subunits.
How is information organized in a DNA molecule?
The information in DNA is contained in the order of the bases, while the basepairing structure allows the information to be copied.
What scientific investigations led to the discovery of DNA’s structure?
Watson and Crick used information from experiments by Chargaff, Wilkins,
and Franklin to the three-dimensional structure of DNA.