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Hershey's work on T2 phage. DNA, not protein is hereditary substance. CONTENT. 1.Hershey History. 2. What is T2??. 3. Infective Cycle. 4. Hershey Chase Experiment. 5. Conclusion. Alfred Day Hershey. His best known experiment is Hershey Chase experiment
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Hershey's work on T2 phage DNA, not protein is hereditary substance
CONTENT 1.Hershey History 2. What is T2?? 3. Infective Cycle 4. Hershey Chase Experiment 5. Conclusion
Alfred Day Hershey • His best known experiment is Hershey Chase experiment • Concerned the replication of genetic structure of viruses 4 Dec. 1908--- 22 May 1997
1934 -1950Teaching and research at the Department of Bacteriology1936Held an instructorship in bacteriology and immunology 1936 -1939Work together with Professor J. J. Bronfenbrenner. 1938Became assistant professor 1942Became associate professor
What is T2 ? • The T2 phage is a strongly toxic bacteriophage and tadpole-shaped virus • small virus that infect only bacteria • Contain 50% DNA and 50% protein
Infect E-coli • Contains linear double-stranded DNA
tail fibers of the phage attach to the bacterial cell to initiate infection
Protein coat of the T2 carries the organ of attachment to bacteria.
The infective cycle of T2 in E.coil • Virus attach to the surface of their host cell(a)
DNA accumulate,other genes are transcribed and translated(C)
Hershey ChaseExperiment • Radioactive Sulphur (35S) non-radioative DNA? • Radioactive Phosphorous(35P) radioactive DNA?
Conclusion DNA is the GENTIC MARTERIAL!!!