Immunology Flashcards
(44 cards)
What is the immune system?
The body’s ability to resist or eliminate potentially harmful foreign materials.
What is immuinity?
Protection from harmful diseases.
Define innate immuinity.
Cells that are always ready to attack.
Why doesn’t innate immuinity always work?
Pathogenic microbes have evolvedto resist innate immuinity.
Define pathogen
Any microorganism that causes harm.
Name five pathogens.
Virus, bacteria, parasites, fungi and protozoa.
Are innate repsonsesspecific?
No, they are non-specific.
describe innate responses.
Innate responses can distinguish between human cells and pathogens but not the type of pathogen. They respond v quickly but have no memory and will create the same response.
How is adaptive immuinity stimulated?
By exposure to a microbe.
Name some external barriers.
Skin, mucus.
Name some of the body’s flushing features.
Saliva, tears, urine.
Describe adaptive immuinity responses.
Slow and can take a few days but remember pathogens.
Name the two types of immuinity.
Innate and adaptive.
Name the two types of inate immuinity.
Humoral and cellular.
Name external barriers relating to the following-
- Sweat
-Stomach
-Tears/ saliva
Sweat- high NaCl, lysozymes.
Stomach- digestive enzymes, gastric acid.
Tears/saliva- lysozymes.
Name some cells which are important in cellular innate immuinity.
Basophils, phagocytes.
Define phagocytes.
Cells which track down, engulf and destroy bacteria and pathogens.
Describe the six stages of phagocytosis.
- Movement of the pathogen towrads the microbe.
- Attachment of microbes to phagoyte surface.
- Endocytosis of microbe and formation of phagosome.
- Fusion of phagosome and lysosome.
- Killing of microbe through digestion by enzymes.
- Discahrge of waste materials.
Describe neutrophils.
Must abundant WBC.
Contains granules filled w many digestive enzymes which kill and destroy bacteria and other pathogens.
Describe monocytes.
Make up 5% of WBC’s.
Larger than neutrophils and can digest a lot more.
Describe macrophages.
Break down pathogens.
They process antigens and present them to the cells of the adaptive immunity to produce specific immune responses in the form of Ab and cytotoxic T cells.
What do CD4 cells do?
CD4 cells help control the activity of other cells and can help with triggering the immune system.
What disease can impact CD4 cells and how?
HIV
infects CD4 cells and makes more copies of itself.
What do CD8 cells do?
CD8 T cells mediate viral clearance by utilizing a variety of effector mechanisms to induce the apoptosis of virus-infected cells
