Hi barbara, let me add something the others have not said yet.
Since a RNA virus is a single chromosome then isn't logical to think that since we have 23 chromosomes X2 each parent that our chromosomes are actually RNA viruses linked together with all of their information put into DNA storage?
RNA has a couple of fundamental differences from DNA:
DNA is composed of the four bases, A, C, G and T, while RNA is composed of the four bases A, C, G and U
quote:The four bases found in DNA are adenine (abbreviated A), cytosine (C), guanine (G) and thymine (T). These four bases are attached to the sugar/phosphate to form the complete nucleotide, as shown for adenosine monophosphate.
quote:RNA is very similar to DNA, but differs in a few important structural details: in the cell, RNA is usually single-stranded, while DNA is usually double-stranded; RNA nucleotides contain ribose while DNA contains deoxyribose (a type of ribose that lacks one oxygen atom); and RNA has the base uracil rather than thymine that is present in DNA.
it is normally a single strand, where DNA is normally a cross-linked double strand, where the cross-links are only between specific molecules, A only cross-links with T, and C only cross-links with G.
This places greater structural & organizational restrictions on DNA than on RNA.
Thus a couple of changes have to happen to RNA to turn it into DNA.