Question

The backbones of DNA and RNA are

A. identical.
B. very different, made of nucleotides in DNA and amino acids in RNA.
C. made of alternating sugars and phosphate groups.
D. made of a chain of base pairs.

Answer 1

The backbones of both DNA and RNA consist of nucleotides made of sugars, phosphate groups, and bases, with DNA using deoxyribose and thymine, whereas RNA uses ribose and uracil, making option C the correct answer.

The backbones of DNA and RNA are composed of a chain of nucleotides, which include a sugar, a phosphate group, and a base. However, the sugar in the DNA backbone is deoxyribose, while in RNA, it is ribose. Moreover, DNA contains the base thymine, unlike RNA, which contains uracil instead of thymine. Therefore, while they have a similar structure regarding their backbone, composed of a sugar-phosphate chain, the precise components and bases do differ between the two.

In conclusion, the backbones of DNA and RNA are made of alternating sugars and phosphate groups, but are not identical due to the differences in the sugar component and the bases they contain. The correct answer to the provided question is C: made of alternating sugars and phosphate groups.

Answer 2

The answer is very likely C.

Step-by-step explanation:

This becomes easy once we remember that DNA and RNA are not identical - which is why they have different names, RNA = 'ribo', DNA = 'deoxy.' This eliminates choice (A). While they are different, they are not incredibly different - DNA and RNA are both made up of nucleotides - they are not however, made up of Amino acids. Amino acids are what they can code for, and subsequently create proteins during protein synthesis. This helps us eliminate (B). Finally, we know that in order for something to have base pairs it needs to be double stranded - which RNA is not. Which means that because RNA is not double stranded (its singly stranded) that the answer cannot be (D). Leaving us with the only plausible option; (C).