Question

select all the correct answers. what are two basic differences between dna and rna? rna is usually single stranded, while dna is usually double stranded. rna contains uracil, while dna contains thymine. rna is usually double stranded, while dna is usually single stranded. rna contains thymine, while dna contains uracil. rna doesnt contain cytosine, while dna doesnt contain adenine.

Explanation:

1. For the first option: RNA's typical structure is single - stranded, and DNA's typical structure is double - stranded (the double - helix structure). This is a well - known difference between them.
2. For the second option: In terms of nitrogenous bases, RNA has uracil (U) instead of thymine (T), while DNA has thymine (T) and not uracil (U).
3. The third option is incorrect because it reverses the strand - structure characteristics of RNA and DNA.
4. The fourth option is incorrect as it swaps the nitrogenous bases of RNA and DNA.
5. The fifth option is incorrect because both RNA and DNA contain cytosine and adenine (RNA has adenine, cytosine, guanine, and uracil; DNA has adenine, cytosine, guanine, and thymine).

Answer:

A. RNA is usually single stranded, while DNA is usually double stranded.
B. RNA contains uracil, while DNA contains thymine.