Next, several biochemical tests are run to further identify the microorganism. Lactose fermentation is run for 24 hours at 37⁰C in lactose broth containing a Durham tube and phenol red indicator. The result shows a red broth with no air bubbles in the Durham tube. What do these results mean in terms of this microorganism’s ability to ferment lactose?

The hershey and chase experiments involved the preparation of two different types of radioactively labeled phage. which of the following best explains why two preparations were required? a. the bacteriophage used in the experiments was a t2 phage. b. it was necessary that each of the two phage components, dna and protein, be identifiable upon recovery at the end of the experiment. c. each scientist had his own method for labeling phage, so each conducted the same experiment using a different isotope. d. establishing the identity of the genetic material required observation of two phage generations.