The first three are the same as those found in DNA, but in RNA thymine is replaced by uracil as the base complementary to adenine. This base is also a pyrimidine and is very similar to thymine. Uracil is energetically less expensive to produce than thymine, which may account for its use in RNA.
There are thousands of bacterial species and they are not identical towards one another, therefore there forms are quite unique. so its just there characteristics that make up how bacteria look like.
Hope this answers your question.
"From the dog" is the prepositional phrase since it begins with the preposition "from" followed by the noun phrase "the dog" .