Term
| Why does AZT not work in the long run? |
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Definition
| The virions eventually become resistant to AZT as a result of their high mutation rate. |
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Term
| What happens when AZT is absent? |
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Definition
| The AZT-resistant virion concentration will decline and the the non-AZT resistant virions will become dominant. |
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Term
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Definition
| Origins for the consumption of chimps in central and west Africa. |
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Term
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Definition
| Origins from the consumption of the sooty mangebey monkey in west Africa. |
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Term
| Why is HIV so hard to treat? |
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Definition
| HIV replicates using the host's DNA and enzymatic components to propagate. Interfering with the virus would also have an effect on the host. |
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Term
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Definition
| AZT was used in efforts to treat HIV by blocking RNA polymerase with the addition of azidothymidine (-N3). |
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Term
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Definition
- Acute phase - initial viral load spike then a rapid decline (0-12 weeks w/ spike at 0-6 weeks).
- Chronic phase - mostly asymptomatic with a low and stable viral load (1-7 years).
- AIDS phase - host immune system collapses and cannot protect itself. Death usually occurs within 3 years (7-11 years).
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Term
| How can HIV be monitored? |
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Definition
| By observing the virion concentration in the bloodstream, lymphoid tissue of the gut. |
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Term
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Definition
| HIV attacks the host's immune cells which cripples their CD4 T cells. Once the concentration of the T cells drop below 200 cells per mL, the AIDS phase begins. |
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Term
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Definition
- Virion encounter T cell
- Virion's gp120 surface protein binds to CD4 then CCR5 of the T cell
- Virion fuses with host and releases its genome and enzymes into the host
- Reverse transcriptase synthesizes DNA from virion RNA
- Integrate splices virion DNA into host's genome
- Virion DNA is transcribed into mRNA using host RNA Polymerase
- mRNA is translated into HIV precursor protein by host's ribosomes
- New generation of virions assemble at host's membrane
- New virions bud from host membrane
- Protease cleaves precursor proteins from mature proteins
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Term
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Definition
- 2 copies of RNA genome
- gp120 - surface protein
- gp41 - anchoring protein
- reverse transcriptase - creates DNA from RNA
- protease - breaks down proteins
- intergrase - allows genetic material to be integrated into host's DNA
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Term
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Definition
| Virus that goes from RNA -> DNA -> mRNA -> protein |
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Term
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Definition
| Via fluid transfer from infected individual to non-infected |
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Term
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Definition
| Changes in frequency of alleles over generations at the population level. |
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Term
| Why is HIV used as a model for studying evolution? |
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Definition
| Because the virus has a short life, high mutation rate and large generation size. |
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Term
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Definition
| Human immunodeficiency virus is an intracellular parasite that invades specific cell types in a host's immune system. |
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