Immune System and Disease
Today, our world is faced with many diseases. Some haven't been discovered and some have no cures. The immune system fights off many of these diseases, but what happens when it fails us? One of the most deadly, incurable disease the world is faced with today is the Human Immunodeficency Virus (HIV). There is no none cure yet.Viruses cause colds and the flu. Viruses are microscopic particles that invade the cells of plants, animals, fungi, and bacteria. They often destroy the cells they invade.How do viruses reproduce? A virus first enters a cell in one of three ways: direct penetration, endocytosis, or membrane fusion. The virus takes over the cell's machinery and is thus forced to make the virus's proteins and RNA. When the virus has entered, viral RNA is released in to the cell and reverse transcriptase occurs. Reverse trancriptase is when the cell makes a DNA copy of the viral RNA. It then produces the proteins and genes the virus needs to be assemble. The virus can then be released by three ways: lytic, lysogenic, and persistent. A virus, although not considered to be alive, does have a life cycle. First the virus attaches to a cell, which it recognizes by its surface markers. Then it penetrates the cel
There are three different stages of HIV. Dendritic cells are special CD4 cells that line the mucus, vigina, penis, and lower rectum. It then assembles itself back together and the new viruses are released. The third: interferon binds to the surface of surrounding healthy cells and activates their genes to create an antiviral state. Anal sex carries a higher risk of getting it than vaginal or oral sex. The second: natural killer cells are non-specific and destroy all infected cells. Once they divide, they are called plasma cells and are able to produce 2,000 antibodies per second for 4-5 days. After the viral DNA has been made the new viruses are assembles and then released by budding. The second line of defense is at these natural openings. The risk is higher for the female because HIV only infects cells that have the CD4 surface marker (semen has a lot of CD4 cells in it and there is not much blood flow in the vagina). HIV is hard to fight because of its antigenetic drift. Next, it replicates and makes copies of itself. You are classified as having full-blown AIDS.
Common topics in this essay:
T4-cells B-cells,
RNA DNA,
Virus HIV,
Tortiory Response,
Africa HIV,
HIV HIV,
HIV Acute,
,
Crisis T4,
Haiti France,
natural openings,
rna dna,
immune system,
blood blood,
infected cells,
surface markers,
viral rna,
skin natural openings,
skin natural,
stop pathogens,
cell cell,
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