Module 2: Historical DNA Experiments and Investigators

Vocabulary practice flashcards covering key historical genetics experiments, investigators, observations, and conclusions from Meischer to Hershey and Chase.

Meischer

First to isolate DNA

Yanofsky

Changes in DNA and protein are colinear

Griffith

Studied whether an extract from dead bacterial cells could genetically transform living cells, observing that while heat-killed S strain or R strain alone did not kill mice, heated S plus R strain killed mice.

Transformation

The unknown process identified by Griffith that changes an avirulent strain of bacteria into a virulent strain.

Avery, Macleod and McCarty

The investigators who sought the cause of transformation by eliminating bacterial components one at a time, DNA is required for transformation.

DNase

The treatment that kept the S cell extract from transforming R cells in the experiments conducted by Avery etc

Hershey and Chase

Asked what the infectious parts of bacteriophages are, radiolabeling protein coats and DNA to determine which component is passed on. DNA is the infectious part of bacteriophages

Chargaff

Did a quantitative analysis of DNA base pair ; G=C (amount) A=T (amount)

Wilkins and Franklin

X-ray crystallography study of DNA ; Structure of DNA is helical w/ more than one helix with repeating patterns

Watson and Crick

What is the structure of DNA? ; Antiparallel strands. Pyrimidines pair with purines. Sugars and phosphates on the outside of the helix. Alternating major and minor grooves