For a science fair project, two students decided to repeat the Hershey and Chase experiment, with modifications. They decided to label the nitrogen of the DNA, rather than the phosphate. They reasoned that each nucleotide has only one phosphate and two to five nitrogens. Thus, labeling the nitrogens would provide a stronger signal than labeling the phosphates. Why won't this experiment 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 et al. have already concluded that this experiment showed inconclusive results.
D) Although there are more nitrogens in a nucleotide, labeled phosphates actually have 16 extra neutrons; therefore, they are more radioactive.
E) Amino acids (and thus proteins) also have nitrogen atoms; thus, the radioactivity would not distinguish between DNA and proteins.

Question

30-12-2018
Biology

contestada

For a science fair project, two students decided to repeat the Hershey and Chase experiment, with modifications. They decided to label the nitrogen of the DNA, rather than the phosphate. They reasoned that each nucleotide has only one phosphate and two to five nitrogens. Thus, labeling the nitrogens would provide a stronger signal than labeling the phosphates. Why won't this experiment 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 et al. have already concluded that this experiment showed inconclusive results.
D) Although there are more nitrogens in a nucleotide, labeled phosphates actually have 16 extra neutrons; therefore, they are more radioactive.
E) Amino acids (and thus proteins) also have nitrogen atoms; thus, the radioactivity would not distinguish between DNA and proteins.

Respuesta :

Otras preguntas

what do bacteria have in common with the cells of other living organisms?

Raul calculated that he would spend $125 on school supplies this year but he accually spent 87.50 on school supplies what is his percent of error

How did the Greeks view the role and limits of government? a. The Greeks believed deeply in the wisdom of kingly rule. b. The Greeks thought citizens should pa

What is the third poncho of the alphabet?

which was not a motivation for European exploration in the fifteenth and sixteenth centuries?

We played all day, talked all night, and generally enjoyed one another's company. How would the above sentence, written in active voice, best be translated i

What can be inferred from these lines describing the pardoner in Chaucer's prologue to The Canterbury Tales? He had a fine veronica sewed to cap. His wallet lay

what is the best way to keep you body healthy

Which word in the sentence is the direct object? Then he made a pot of stew with the leftovers from dinner. a. dinner b. stew c. leftovers d. pot

During meiosis, genetic recombination may occur more than once through the process of ____________________, resulting in an increase in genetic variability.

JuliettaGlassford JuliettaGlassford · Answer 1 · 2019-01-10T07:44:55+01:00

Answer is (E) : Amino acids (and thus proteins) also have nitrogen atoms; thus, the radioactivity would not distinguish between DNA and proteins.

Let me explain you why. Hershey and Chase conducted their experiment to show what is the genetic material that passes from one generation to another generation. Is it protein or DNA? For explaining this, they allowed the virus to grow in the presence of two different radio active elements.

In one set they grew viruses in the presence of P-32 radio-active element

In another set they grew viruses in the presence of S-35 radio active element.

The reason why they choose these two radio-active element was, phosphorus is present in DNA but not in proteins and similarly sulphur is found in proteins but not DNA.

These viruses were allowed to infect bacteria and the later was observed to be radio-actively labelled with P-32 but not S-35. This clearly showed that DNA is the genetic material which was passed from virus to bacteria.

Now if you choose Nitrogen for labeling, it won't help you in getting any conclusion since nitrogen is present in both proteins and DNA.