What were the findings of Hershey and Chases experiments with bacteriophages
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If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked. There were many scientists who knew that the element essential for inheritance is found within the body of an organism, but they failed to discover it. Many experiments were performed to extract the chromosomal components, but the question of inheritance remains unanswered. However, with the advent of Griffith’s experiments, the path was opened for the discovery of genetic material. Working off on Griffith's experiment, Avery and his colleagues successfully isolated DNA and demonstrated that DNA is the genetic material. However, until Hershey and Chase published their experimental data, not everyone agreed with this theory. The Hershey and Chase ExperimentHershey and Chase Experiment Diagram
Why is DNA Considered a Genetic Material?It was discovered that DNA dominated the genetic makeup of the majority of species. There were notable exceptions, including certain viruses whose genetic makeup was RNA. But what distinguishes DNA from other molecules such as proteins, carbohydrates etc. as genetic material? Important requirements for being a genetic material are:
The majority of other compounds, including proteins, carbohydrates and lipids, did not meet the aforementioned requirements. Although RNA could meet the requirements, DNA remained the favoured genetic material over RNA for the following reasons:
Pulse Chase ExperimentThe Pulse-Chase Analysis is a technique used in Biochemistry and genetic experiments to look at the biological activity that is happening over time by exposing the cells to the same substance first in a labelled form (the pulse) and then in an unlabelled form (the second pulse) (chase). This technique can be used to track a cell's activity over an extended period of time. Protein kinase C, ubiquitin and numerous other proteins have been studied using this technique. The technique was additionally employed to demonstrate the existence and utility of Okazaki fragments. To clarify the secretory process, George Palade used a pulse-chase of radioactive amino acids. ConclusionAlfred Hershey and Martha Chase carried out a series of tests in 1952 that helped to establish that DNA is the genetic material. These investigations are known as the Hershey-Chase experiments. Despite the fact that DNA has been known to biologists since 1869, many scientists at the time still believed that proteins contained genetic information because DNA seemed to be less complex than proteins. In their tests, Hershey and Chase demonstrated that when bacteriophages, which are made up of DNA and protein, infect bacteria, only a small portion of their protein actually reaches the host bacterial cell. The prior, current and later discoveries all served to indicate that DNA is the hereditary material, even though the results were inconclusive and Hershey and Chase were circumspect in their interpretation. Max Delbruck, Salvador Luria and Hershey received the 1969 Nobel Prize in Physiology or Medicine for their discoveries relating to genetics. What did Hershey and Chase discover about bacteriophages?Hershey and Chase figured that the virus transferred genetic material into the bacterium to direct the production of more virus. 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.
What was the result of Hershey and Chase's experiment?Hershey and Chase concluded that protein was not genetic material, and that DNA was genetic material.
What were the results of Hershey and Chase experiment quizlet?What were their conclusions? This indicated that the protein coat of the phage remained outside the cell, and that it is not involved in the production of new phages. Importantly, they showed that phage DNA enters the host cell and directs phage reproduction.
What results would you expect if the bacteriophage that Hershey and Chase used in their experiment had contained RNA instead of DNA?What results would you expect if the bacteriophage that Hershey and Chase used in their experiment had contained RNA instead of DNA? The results would be the same.
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