An animal is called a protostome or a deuterostome based on an animal is called a protostome or a deuterostome based on the presence or absence of a mouth the way its body cavity develops whether it has a body cavity the number of germ lay

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.