Immunology Flashcards
What is meant by tolerance?
Immunological unresponsiveness to an antigen.
What are the main physical barriers to infection?
Reproductive, respiratory and digestive tract and the skin.
What cells produce mucus?
Goblet cells
Into what two sections is the immune system divided?
Innate and adaptive.
Which cells are phagocytic?
Monocytes, dendritic cells and macrophages
All granulocytes
Describe the process of phagocytosis.
Phagocyte surrounds and engulfs bacterium, encasing it in intracellular phagosome.
Lysosome containing cocktail of powerful hydrolytic enzymes fuses with phagosome.
Enzymes digest bacterium, destroying it.
Debris is released into extracellular space by exocytosis and acts as a signal to other immune cells.
Into what two cell types can a monocyte mature?
Dendritic cells
Macrophages
What is the most abundant WBC?
Neutrophil
For how long do neutrophils generally circulate in the blood before undergoing apoptosis?
6 Hours
Where are all blood cells produced?
Bone marrow
In what type of infection are eosinophils mainly involved?
Parasitic
What type of WBC is a mast cell?
Granulocyte
What type of hypersensitivity are mast cells involved with?
Type 1- Allergy
What is the least common granulocyte cell?
Basophil
Name 4 non-specific humoral molecules which protect against infection.
- Lysins
- Growth inhibitors
- Enzyme inhibitors
- Complement proteins
What causes redness upon injury?
When macrophages encounter a pathogen, they release chemicals to alert other cells to invasion. These chemicals often restrict blood flow away from the site of invasion. This causes redness
Describe the adaptive immune system.
Specific- Exhibits immunological memory and antibody production
Describe the innate immune system.
Non-specific- Produces the same response for every infection.
What are the three compliment pathways.
Classical
Alternative
Lectin
Give a brief overview of the complement pathway.
Over 20 individual proteins, working together in an enzyme cascade to form a membrane attack system. This basically works by punching a hole in the pathogen, preventing it from maintaining homeostasis and killing it.
What is the argument for the complement system being part of the innate immune system?
It does not change its mechanism at all over time, with subsequent infections.