What observation did Griffith make in his experiments with Streptococcus pneumoniae?
What observation did Griffith make in his experiments with Streptococcus pneumoniae? The mouse did not survive when injected with a mixture of live, avirulent (smooth) Streptococcus pneumoniae and heat‑killed, virulent Streptococcus pneumoniae.
Which was a conclusion of Griffith’s work with Streptococcus pneumoniae?
Discovered DNA as a genetic material & two strains of bacteria, streptococcus pneumoniae, causes pneumonia. One stranded could be transformed or changed into the other form. One has a smooth strain and one is a rough strain. He concluded that there had been a transformation from live R bacteria to live S bacteria.
What happened in Frederick Griffith’s experiment with pneumonia and mice?
What happened in Frederick Griffith’s experiment with pneumonia and mice? He worked with viral S and nonviral R strains of Pneumococcus bacteria by injecting them into healthy mice. He injected both strains separately and the mice with disease causing bacteria died others didn’t.
What was the conclusion of Avery’s experiment?
Avery and his colleagues concluded that protein could not be the transforming factor. Next, they treated the mixture with DNA-destroying enzymes. This time the colonies failed to transform. Avery concluded that DNA is the genetic material of the cell.
Why did Hershey and Chase use a blender?
After introducing to the phage culture to the bacterial sample, they used a Waring blender to violently disturb the infected bacteria, causing the protein shells to detach from their hosts
Why did Hershey and Chase use phosphorus and sulfur?
Why were phosphorus-32 and sulfur-35 perfect for what Hershey & Chase were investigating in their experiments? They were perfect because proteins contain almost no phosphorus and DNA contains no sulfur, so the radioactive isotopes would show up in the cells if the phosphorus-32 or sulfur-35 appeared.
What does the T2 phage infect?
Enterobacteria phage T2 is a virus that infects and kills E. coli. The injected DNA molecules cause the bacterial cells to produce more viral DNA and proteins. These discoveries supported that DNA, rather than proteins, is the hereditary material.
Is protein or DNA the genetic material of phage T2?
The Hershey-Chase experiment, which demonstrated that the genetic material of phage is DNA, not protein. The experiment uses two sets of T2 bacteriophages. In one set, the protein coat is labeled with radioactive sulfur (35S), not found in DNA.
Which type of virus was used in Hershey Chase experiment?
Why were bacteriophages used in the Hershey Chase experiment quizlet?
Importantly, they showed that phage DNA enters the host cell and directs phage reproduction. This showed that DNA was the genetic material that was passed down from the virus to a cell and thus DNA was the material that is passed from a cell to another cell.
Which was the first genetic material?
Is RNA more stable than DNA?
While DNA contains deoxyribose, RNA contains ribose, characterised by the presence of the 2′-hydroxyl group on the pentose ring (Figure 5). This hydroxyl group make RNA less stable than DNA because it is more susceptible to hydrolysis.
Who proved RNA as genetic material?
What can RNA do that DNA Cannot?
DNA has four nitrogen bases adenine, thymine, cytosine, and guanine and for RNA instead of thymine, it has uracil. Also, DNA is double-stranded and RNA is single-stranded which is why RNA can leave the nucleus and DNA can’t. Another thing is that DNA is missing an oxygen.
Why RNA was the first genetic material?
RNA is the first genetic material in cells because: RNA is capable of both storing genetic information and catalyzing chemical reactions. Essential life processes like metabolism, translation, splicing, etc. evolved around RNA.
Is RNA self replicating?
An RNA enzyme has been developed that catalyzes the joining of oligonucleotide substrates to form additional copies of itself, undergoing self-replication with exponential growth