In step number four, right within the cytoplasm of that human cell, these reverse transcriptase enzymes basically transcribe the RNA into DNA and we form the viral double stranded DNA as shown in blue. So we form one and two strands and then they basically fuse to form our double stranded DNA, the viral double stranded DNA. Now, in step five we have the viral double stranded DNA, then basically travels into the nucleus of that cell and in the nucleus of that cell, another special type of enzyme known as retroviral integrates or simply integrates, acts to basically integrate or incorporate that viral double stranded DNA shown in blue into the DNA genome of that human cell. Now, once that actually takes place, we move on to step six. So in step six, the cell then transcribes the viral DNA back into the viral RNA as well as viral mRNA that can be used to synthesize viral proteins. So in step six, we see that the ribosomes of our human cell basically use the mRNA, the viral mRNA, to produce special types of proteins that need to be used by the new HIV system, by the new virus, the HIV system.