Question

Is my reasoning correct? Will leave rate and comment.

1. Griffiths (1928) mixed heat-killed 'THIS' bacteria with 'IIR' bacteria and injected a mouse with both types of bacteria. As a result, the mouse died and Griffiths obtained living 's bacteria from the dead mouse. How can you explain this phenomenon? When 'R' and 'strains were mixed, the DNA from 'IS' bacteria with the gene responsible for forming capsules transferred to the 'R' bacteria. The gene cause 'R' to transform into 'IS' creating a capsule to overtake the mouse's immune system. 2. For each test tube in the Avery, Macleod, and McCarty experiment, circle the macromolecules from the Type IIIS strain filtrate that you would expect to be found in the test tube after the treatment. Circle 'None" if none of the macromolecules are present. Tube A: No filtrate RNA DNA Protein None RNA DNA Protein None Tube B: No enzyme Tube C: RNase RNA DNA Protein None RNA DNA Protein Tube D: Protease Tube E: DNase None None RNA DNA Protein 3. If the contents of each tube were injected into the mouse, which ones would kill the mouse and why. Tubes B, C, and D contents would kill the mouse because the changing of DNA is evident. This conclusion can be backed by the presents of DNA in tubes By Cand D DNA s changed to which it becomes a virulent bacterium, thus making it harmful to the mouse's immunity

Answer 1

Yes reasoning for all the questions are correct.

1. This question explains the tranformation principle of Griffith's experiment. Transformation of gene from the heat killed S (smooth) strain to live R strain (rough) happened here. So the R strain turned to S strain and became virulent to the mouse thereby caused death.

2 & 3. Avery et al took the griffith's transformation principle and treated it with various reagents (RNase, DNase and protease) and injected them into mouse after each treatment.

Mouse dead after Rnase and protease treatments but survived after DNase traetment. This confirms that the DNA (genetic material) is the cuase for the transformation of non virulent strain to virulent strain and caused the death in mouse.

RNase degrades RNA = mouse dead

Protease degrades protein = mouse dead

DNase degrades DNA = mouse survived

So filtrate from tubes B, C and D kill bacteria and tube E did not kill bacteria.