Question

2. While looking at a cell under a microscope, a scientist is able to see a biological molecule. This molecule is a nucleic acid with a ladder structure and contains the nitrogenous bases adenine, thymine, cytosine, and guanine. Based on this information, what conclusion can the scientist draw regarding this nucleic acid?
(A)The nucleic acid is DNA and would be found in the cell’s nucleus.
(B)The nucleic acid is DNA and would be found in the cytoplasm.
(C)The nucleic acid is RNA and would be found in the cytoplasm.
(D) nucleic acid is RNA and would be found in the cell’s nucleus. ...?

Answer 1

The correct answer is A

The scientist can determine that this nucleic acid is a DNA molecule, because it contains Thymine, which does not occure in the RNA molecule. The RNA molecule contains Adenine, Guanine and Cytosine just like the DNA, but unlike the DNA it contains Uracil, not Thymine.

Secondly, the scientist can say with certainty that this DNA molecule is surrounded by a nucleus based on the structure of the nucleic acid described. Only eukaryotic cells have ladder structure. The prokaryotic cells have circular DNA and do not have any organelles, like the nucleus. Therefore, from the ladder structure of the DNA the scientist can see that the cell has a nucleus.

Answer 2

Based on the given description above, the correct answer would be option A. The conclusion that the scientist can draw regarding this nucleic acid is that the nucleic acid is DNA and would be found in the cell’s nucleus. Not RNA since RNA has Uracil instead of Thymine and DNA is always in the nucleus. Hope this answer helps.