BIOLOGY
STRUCTURE OF NUCLEIC ACIDS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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only the marked Sulfur showed up in the pellet, showing that DNA got into the bacteria
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only the marked Phosphorous showed up in the pellet, showing that DNA got into the bacteria
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only the marked Sulfur showed up in the supernatant, showing that the protein dd not get into the bacteria
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only the marked Phosphorous showed up in the supernatant, showing that the protein did not get into the bacteria
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Detailed explanation-1: -The protein shell of the virus was tagged with radioactive sulphur, and this ended up in the supernatant. The heavier bacterial cells formed the pellet, so Hershey and Chase knew that DNA was the genetic material of the virus, as the phosphorus was found there.
Detailed explanation-2: -In their experiments, Hershey and Chase showed that when bacteriophages, which are composed of DNA and protein, infect bacteria, their DNA enters the host bacterial cell, but most of their protein does not. Hershey and Chase and subsequent discoveries all served to prove that DNA is the hereditary material.
Detailed explanation-3: -Hershey and Chase established whether the phage injected DNA or protein into host bacteria. They prepared two samples of phage: ³⁵S, which labels protein and ³²P, which labels DNA. It was found that only ³²P entered the bacterial cells, indicating that DNA, not protein, is the genetic material.