High School

When performing a bacteriophage sensitivity test, you streak the phage on the plate first, and the bacterial strain second.

A. True
B. False

Answer :

The correct order in a bacteriophage sensitivity assay is to prepare a bacterial lawn first and then apply the phage lysate. The sequence provided in the question is false. Therefore, the above statement is false.

The statement that you streak the phage on the plate first and the bacterial strain second when doing a bacteriophage sensitivity plate is false. In a typical bacteriophage sensitivity assay, a bacterial lawn is prepared first to ensure that there is a uniform layer of bacteria. Only after this bacterial lawn has been established do you apply the diluted solutions of your phage lysate to the plate. These phage will then infect, replicate within, and lyse the bacteria, creating clear zones known as plaques where bacteria have been destroyed. This allows for the titering of recombinant phage clones, determining the number of phage particles present, and understanding viral titers in relation to their lytic abilities.