So DNA viruses are predominantly in the double stranded form. They have double stranded DNA while RNA viruses predominantly comes in the single stranded RNA form. Now DNA replication occurs in the nucleus while RNA transcription replication takes place within the cytoplasm of our cell. And finally DNA viruses must first transcribe DNA into RNA before the proteins can actually be synthesized. However, for RNA viruses they basically contain the RNA that can be used pretty much directly to synthesize our protein. So we see our RNA viruses basically bypass the DNA to RNA transcription process.