Why did Hershey and Chase used radioactive sulfur and phosphorus in their experiment?
What technique did Hershey and Chase use to study the viruses in their experiments? They used radioactive isotopes of phosphorus-32 and sulfur-35 as markers so they could trace the proteins and DNA to see what they were doing to the cell.
What is the reason behind radioactive phosphorus to label DNA and not radioactive sulfur?
They knew that bacteriophage T4 was made of protein and DNA. They also knew that proteins contain sulfur atoms but no phosphorus, while DNA contains a great deal of phosphorus and no sulfur. They used radioactive sulfur and phosphorus to label and, so, distinguish viral proteins from viral DNA.
What did the Hershey Chase experiment prove?
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 bacteria killed the mice in Griffith’s transformation?
Transformation Experiment. Pneumococcus bacteria include two strains, a virulent S strain with a Smooth glycoprotein coat that kills mice (left), and a non-virulent R Rough strain that does not (middle). Heating destroys the virulence of S (right).
What happened when Griffith injected mice with the harmless R strain bacteria alone group of answer choices?
When Griffith mixed heat-killed, harmful bacteria with live, harmless bacteria and injected the mixture into mice, the mice died. In Griffith’s experiment, he mixed heat-killed S-strain bacteria with live, harmless bacteria from the R-strain.
What happened when Griffith injected mice with harmless R strain bacteria?
Griffith had discovered that he could convert the R strain into the virulent S strain. After he injected mice with R strain cells and, simultaneously, with heat-killed cells of the S strain, the mice developed pneumonia and died. In their blood, Griffith found live bacteria of the deadly S type.
Is RNA less stable than DNA?
Unlike DNA, RNA in biological cells is predominantly a single-stranded molecule. This hydroxyl group make RNA less stable than DNA because it is more susceptible to hydrolysis. RNA contains the unmethylated form of the base thymine called uracil (U) (Figure 6), which gives the nucleotide uridine.
Why DNA is stable than RNA?
Due to its deoxyribose sugar, which contains one less oxygen-containing hydroxyl group, DNA is a more stable molecule than RNA, which is useful for a molecule which has the task of keeping genetic information safe. RNA, containing a ribose sugar, is more reactive than DNA and is not stable in alkaline conditions.
What is RNA vs DNA?
There are two differences that distinguish DNA from RNA: (a) RNA contains the sugar ribose, while DNA contains the slightly different sugar deoxyribose (a type of ribose that lacks one oxygen atom), and (b) RNA has the nucleobase uracil while DNA contains thymine.
What makes DNA more stable?
The main bonding in DNA which renders the double helix structure so stable is that of hydrogen bonds. Between the complementary base pairs, hydrogen bonds connect the two strands of the helix.