Question

Match the scientists to their experiment and fill out the key finding of the experiment.

A. Hershey-Chase
B. Griffith
C. Meselson-Stahl
D. Avery, MacLeod & McCarty Scientist
1) Infected mice with two different strains of Streptococcus pneumoniae. Some mice were injected with only live S strain), some with only live R strain, some with only heat killed S strain, and some with heat killed S and live R strain
2)Tested three possible models of DNA replication by growing bacteria in heavy nitrogen media then shifting them to light nitrogen media
3) Labeled bacteriophages with S35 and P32 and allowed the labeled phages to infect bacteria
4)Infected mice with two different strains of Streptococcus pneumoniae, heat killed S strain and live R strain. Used enzymes to degrade biological molecules in S strains. Enzymes include protease, ribonuclease, and deoxyribonuclease.

Answer 1

Griffith's experiment involved transforming R strain bacteria into virulent S strain in mice, Avery, MacLeod & McCarty used enzyme degradation to identify DNA as the genetic material, Meselson-Stahl showed DNA replication is semiconservative, and Hershey-Chase confirmed DNA as the genetic material using labeled bacteriophages.

Step-by-step explanation:

To match the scientists with their experiments and summarize the key findings:

• Griffith - Scientist 1) Infected mice with two different strains of Streptococcus pneumoniae. The key finding was that the heat-killed S strain seemed to "transform" the harmless R strain into the deadly S strain, suggesting the transfer of genetic material.
• Avery, MacLeod & McCarty - Scientist 4) Used enzymes to degrade biological molecules in heat-killed S strains of Streptococcus pneumoniae. The key finding was that DNA is the molecule responsible for transformation, thus indicating that DNA is the genetic material.
• Meselson-Stahl - Scientist 2) Tested three possible models of DNA replication using heavy nitrogen media. They concluded that DNA replication is semiconservative, where each of the two parent DNA strands serves as a template for new DNA strands.
• Hershey-Chase - Scientist 3) Labeled bacteriophages with S35 and P32 to infect bacteria. Their key finding was that DNA, not protein, enters bacteria during infection and directs the formation of new viruses, further confirming that DNA is the genetic material.