Hello, I am having trouble coming up with the correct answers regarding the foll

Question

Hello, I am having trouble coming up with the correct answers regarding the following questions for a DNA Hydrolysis Lab in Chemistry.
*In the TLC Image, the spot at the very bottom is Thymine. So, from bottom to top, it's Thymine, Adenine, Guanine and the spot at the very top is DNA Extract sample.*                                       
I completed my experiment successfully, but I am stuck on the following questions:
1. After acidifying and reheating the DNA sample, there is a fourth spot on the TLC Image that doesn't match any of the standards. Which is a reasonable conclusion?
   A. There is a very high concentration of thymine that causes an extra spot on the TLC Plate. (I excluded this answer because the spot is closer to Adenine)
   B. The new spot is due to a DNA-Histone Complex. (I am not sure about this one because acid was used in the experiment to break down DNA chains and histone complexes, but would it show up on the TLC plate?)
   C. The new spot is due to the nucleobase cytosine. (I think this is a possibility because other nucleobases may be present in the DNA sample).
   D. The new spot is due to a new glycosodic bond formation.
   E. The new spot is due to a contaminant present in the elution solvent.
2. What is expected if all of the glycosodic bonds in DNA were hydrolyzed?
   A. Only the DNA-histone complex would be present in the sample.
   B. More than 20 different nucleobases present in the solution and numerous spots on the plate. (I think this is a possibility because it would be broken down into smaller molecules).
   C. A very high concentration of thymine and adenine, but no cytosine, in the sample analyzed by TLC.
   D. A high solution concentration of either thymine and adenine, or cytosine and guanine, but not for all nucleobases.
   E. A high concentration of all nucleobases in solution.
3. Suppose that after heating the acidified DNA sample at 95 degrees Celsius for 12 hours, none of the TLC spots observed previously for nucleobases are present. Which of the following would be a reasonable explanation?
   A. No free nucleobases were generated during heating.
   B. The nucleobases are degraded into smaller molecules after long heating in acid.
   C. More than 20 different nucleobases are now present in the solution, so the spots have joined into a continuous streak on the TLC plate.
   D. The DNA-histone complex cannot be hydrolyzed under the new conditions. (I think this is a possibility because of the 12 hour time spent heating).
   E. The Rf values for nucleobases are changed by long heating.
   F. A high concentration of all the nucleobases remains in solution.

Explanation / Answer

1. The answer would be C because after second heating and acid hydrolysis the fourth nucleobase base cytosine was released from the DNA molecules. In otherword first hydrolysis reaction was not complete.

2. The answer is E because complete hydrolysis would result in the removal of all bases from DNA molecules and hence their high concentrations.

3. Answer would be A because after negative spot detection is due to absence of free bases in the solution.

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