Question

For a science fair project, two students decided to repeat the Hershey and Chase experiment, with modifications. They decided to label nitrogen of the DNA, rather than the phosphate. They reasoned that each nucleotide has only one phosphate and two to five nitrogens. Thus, labeling nitrogens would provide a stronger signal than labeling phosphate Why won't this work?
A) There is no radioactive isotope of nitrogen
B) Radioactive nitrogen has a half-life of 100,000 years, and the material would be too dangerous for too long
C) Avery, MacCloud and McCarty already did this
D) Although their are more nitrogens in a nucletotide, labeled phosphates actually have 16 extra neutrons; t Shift Ctrl herefore, they are more radioactive
E) Amino acids (and thus and proteins proteins) also have nitrogen atoms;

Answer 1

Answer:

The correct answer will be option-E

Explanation:

Hershey and Chase's experiment was performed to test whether DNA serves as the genetic material or protein.

To perform experiment they grew bacteriophage into radiolabeled phosphorus and sulfur compounds. The phosphorus is an integral part of the structure of DNA whereas proteins contain sulfur in their structure.  

In the given condition if radiolabeled nitrogen is utilized then the experiment will fail as the structure of proteins also contains an amino group( NH₂) in their structure as well as DNA. The scientist will not be able to identify whether the DNA is the genetic material or protein.

Thus, option-E is the correct answer.