Final answer:
HIV infection of a CD4 cell involves the attachment, fusion, DNA copying, integration, and transcription of the virus.
Step-by-step explanation:
When HIV infects a CD4 cell, it goes through several stages that have consequences at a cellular level:
- The viral particle attaches to the CD4 receptor on the cell membrane and fuses with it.
- The viral RNA is copied into a complementary DNA strand by reverse transcriptase.
- A double-stranded viral DNA is formed.
- The viral DNA is integrated into the host cell's genome by integrase.
- Transcription factors in activated T cells allow the viral DNA to be transcribed into mRNA, leading to the production of new virus proteins and genomes.