End Show Slide 1 of 31 Copyright Pearson Prentice Hall I will understand that compromised immune...
17
End Show Slide 1 of 31 Copyright Pearson Prentice Hall I will understand that compromised immune systems may be unable to fight usually benign pathogens. MT: Immune System Human Immunodeficiency Virus
-
Upload
clifton-wilkerson -
Category
Documents
-
view
214 -
download
1
Transcript of End Show Slide 1 of 31 Copyright Pearson Prentice Hall I will understand that compromised immune...
End Show
Slide 1 of 31
Copyright Pearson Prentice Hall
I will understand that compromised immune systems may be unable to fight
usually benign pathogens. MT: Immune System
Human Immunodeficiency Virus
End Show
40-3 Immune System Disorders
Slide 2 of 31
Copyright Pearson Prentice Hall
Autoimmune Diseases
What is an autoimmune disease?
When the immune system attacks the body's own cells, it produces an autoimmune disease.
End Show
40-3 Immune System Disorders
Slide 3 of 31
Copyright Pearson Prentice Hall
Autoimmune Diseases
Some examples of autoimmune diseases include:
• Type I diabetes attacks insulin-producing cells.
• Rheumatoid arthritis attacks connective tissues around joints.
• Multiple sclerosis (MS) destroys functions of brain and spinal cord neurons.
End Show
40-3 Immune System Disorders
Slide 4 of 31
Copyright Pearson Prentice Hall
AIDS
In 1983, researchers identified the cause of AIDS—a virus that is caused by the HIV for human immunodeficiency virus.
HIV is a retrovirus—a virus that carries its genetic information in RNA, rather than DNA.
End Show
40-3 Immune System Disorders
Slide 5 of 31
Copyright Pearson Prentice Hall
AIDS
HIV attacks and destroys helper T cells (good cells).
As the number of helper T cells decreases, the body becomes more susceptible to other diseases.
End Show
40-3 Immune System Disorders
Slide 6 of 31
Copyright Pearson Prentice Hall
HIV Infection
End Show
40-3 Immune System Disorders
Slide 7 of 31
Copyright Pearson Prentice Hall
AIDS
Reverse transcriptase enzyme
Envelope
Virus attaches to host cell membrane by recognizing specific molecules on the cell surface.
Viral RNA
Capsid
Protein coat
1
1
End Show
40-3 Immune System Disorders
Slide 8 of 31
Copyright Pearson Prentice Hall
AIDS
Viral coat fuses with cell membrane and viral RNA enters the cell
2
2
End Show
40-3 Immune System Disorders
Slide 9 of 31
Copyright Pearson Prentice Hall
AIDS
Viral RNA is used as a template to make viral DNA.
3
3
End Show
40-3 Immune System Disorders
Slide 10 of 31
Copyright Pearson Prentice Hall
AIDS
Viral DNA enters nucleus and attaches to host chromosome. There it may remain dormant (lysogenic cycle) or begin directing the synthesis of viral mRNA (lytic cycle).
4
4
End Show
40-3 Immune System Disorders
Slide 11 of 31
Copyright Pearson Prentice Hall
AIDS
Viral mRNA directs the host cell to assemble viral proteins.
55
End Show
40-3 Immune System Disorders
Slide 12 of 31
Copyright Pearson Prentice Hall
AIDS
Capsids are assembled around the viral proteins and RNA. The new viruses bud off from the host cell membrane ready to infect other T cells.
6
6
End Show
40-3 Immune System Disorders
Slide 13 of 31
Copyright Pearson Prentice Hall
AIDS
Transmission of HIV
HIV is not transmitted through casual contact.
HIV can only be transmitted through the exchange of blood, semen, vaginal secretions, or breast milk.
End Show
40-3 Immune System Disorders
Slide 14 of 31
Copyright Pearson Prentice Hall
AIDS
How can AIDS be prevented?
End Show
Slide 15 of 31
40-3 Immune System Disorders
Copyright Pearson Prentice Hall
AIDS
Preventing HIV Infection
The only no-risk behavior with respect to HIV and AIDS is ABSTINENCE.
-Don’t do drugs (so you don’t share needles)
-Don’t have unprotected sex (so you don’t exchange semen, vaginal fluid, or blood)
End Show
40-3 Immune System Disorders
Slide 16 of 31
Copyright Pearson Prentice Hall
AIDS
Can AIDS Be Cured?
At present, there is NO CURE NO CURE for AIDS.
The virus can be controlled by expensive multidrug and multivitamins that fight the virus.
End Show
40-3 Immune System Disorders
Slide 17 of 31
Copyright Pearson Prentice Hall
AIDS
Does a person die from HIV or AIDS?
Directly no. The virus attacks the immune system, so when a usually benign pathogen (common cold, pneumonia, bacteria) enters the body, the immune system cannot fight it off, and thus leads to death.
