HIVsteps/Life Cylce Of HIV

Question 1

1. Binding/ Attachment

Answer 1

HIV virus has glycoproteins that bind with CD4(helper T cells) receptors in CD4 (helper T cells)

Question 2

2. Fusion

Answer 2

Has blinded to CD4 (Helper T cells)

HIV viruses fuses with the cells

Releases it’s RNA and Viral enzymes into host cell

Question 3

3. Reverse Transcription/DNA Synthesis

Answer 3

HIV RNA uses enzyme reverse transcriptase

Single- Stranded HIV RNA ➡️ Double- Stranded HIV DNA

Conversion to Double- Stranded HIV DNA carries instructions for viral replication

Question 4

4. Integration

Answer 4

HIV DNA enters host cell’s nucleus to combine with their genetic material

Once inside, It releases HIV integrase (enzyme)

This enzyme is used to integrate the viral DNA into healthy DNA of the CD4 “host” cell

This is means PERMANENT infection

Question 5

5. Replication (called Transcription & Translation in the book)

Answer 5

“Virus Factory”

Begins to replicate within the cell

Makes long chain of RNA HIV proteins that are too long to be infectious yet

Building block for MORE HIV

Question 6

6. Assembly/ Cleavage

Answer 6

HIV proteins move to surface of the CD4 “host” cell and releases Protease (an enzyme)

Protease breaks up the long HIV protein chains into smaller ones

This allows them to be able infect other CD4 cells

Question 7

7. Budding

Answer 7

HIV proteins push themselves out of the host CD4 cell

Destroying the host cell

These HIV proteins go on to infect other CD4 cells

Question 8

How many CD4 cells can HIV destroy in a day?

Answer 8

1 billion

Question 9

How many years can your body replace the CD4 cells that HIV destroys?

Answer 9

10-15 years

Key can maintain CD4 cell levels stable