Question

why in retrovirus mRNA first makes DNA then again mRNA then protein why not directly protein from mRNA which is present as its genetic material?

Answer 1

Retrovirus is an RNA virus which contains a specific enzyme called reverse transcriptase that catalyzes the reverse transcription of RNA into DNA. DNA again undergoes transcription to form RNA which translate into specific protein. As reverse transcription lacks proof reading process of DNA replication retrovirus mutates very often and for this reason this virus can easily transform a normal healthy cell into cancer cell.