Question

Biology -> Genetics

Which of the following is a key aspect of the Hershey-Chase bacteriophage experiments?

Group of answer choices

all of the answers are correct

If RNA is destroyed cells are transformed, rough bacteria do not kill mice

labeling of components 32P only into DNA; only 32P enters cells and is passed on to progeny phage

If DNA is destroyed cells are not transformed, only smooth bacteria kill mice

Answer 1

The key aspect of the Hershey-Chase bacteriophage experiment is labelling of components 32P only into DNA; only 32P enters cells and is passed on to progeny phage.

Because in Hershey-Chase experiment, Hershey and Chase take a bacterial cells and it divide into two different testtube. In first testtube, bacterial cells are were grown with radioactive sulfur(35S) which was incorporated into the phage protein. In second testtube, bacterial cells were grown with radioactive phosphorous(32P) which was incorporated into the phage DNA. Different radiolabelled substance incorporation was performed to determine which of the two substance is genetic material. In this experiment, first bacteriophages are mixed with bacteria and phages are allowed to cause infect the bacterial cells. Then this mixture was put in a blender and centrifuged to seperate. Now measured the radioactivity of supernatant and pellet. Supernatant contains free phage, phage proteins and phage parts and pellet contain cells. In first testtube, radioactivity was found in supernatant means none of the sulfur had entered the cells so no phage protein is not entered also in the cell. In second testtube, radioactivity is found in pellet only so, radiolabelled phosphorous entered into the cell which means DNA entered into the cell because during causing infection phage inserts their DNA only into the bacterial cells which is passed on to progeny phage.

(Radioactive protein) 335 containing phage blending, centrifugation (radioactivity) superndant Testtube I • pellet no radioactivity (Radioactive DNA P32 containing phage blending, centrifugation no radioactivity supernatant Testtube a pellet Radio Live) Condusisut DNA is the genetie material, Radioactivity (P32 DNA) found in pellet, DNA can entered into cells and passes progeny phage. on to

Second and fourth options are not correct because these statement are not related with this experiment. This are about Avery, MacLeod, McCarty Experiment.