The Body's Defense Mechanism Flashcards
Exam 4
What are the mechanisms the body uses to defend itself?
- Nonspecific Mechanism
- Specific Mechanism
How many mechanisms does the body use to defend itself?
two
What is an antigenic molecule?
one that stimulates the secretion of antibodies (Ab)
Recognition Concept
when antigens enter the body, first thing the body tries to do is recognize them
What is another name for antibody?
immunoglobulin (Ig)
How many classes of immunoglobulins are there?
And what are they?
- 5
- IgA
- IgD
- IgE
- IgG
- IgM
What is the function of IgE?
- responsible for allergies, releasing histamine
- parasitic infection
- monomer
What is the function of IgA?
- primary antibody in secretions
- found in saliva, breast milk,
- dimer
What is the function of IgG?
- usually produced first during immune reaction
- crosses the placenta (from mother to fetus)
- monomer
What is the function of IgM?
- good for bacteria agglutination (binding/clumping)
- pentomer
- too big to pass through placenta (opposite of IgG)
What is the function of IgD?
- helps the B cells to recognize antigens
- membrane-bound monomer
What are other terms for Nonspecific Mechanism?
- Innate Immunity
- Natural Immunity
- Genetic
What are other terms for Specific Mechanism?
- Acquired Immunity
- Adaptive Immunity
What is an example of a disease required adaptive immunty?
AIDS
How many lines of barrier are there?
AKA?
- AKA lines of defense
- 3 of them
Which line of defense belongs to the specific mechanism?
3rd line of defense/barrier
What are examples of the first line of defense? (11)
- skin
- sweat
- tears
- saliva
- coughing
- sneezing
- blinking
- vomiting (anti-peristalsis)
- nasal hairs
- shedding of skin cells
- stomach acid
What is secreted by saliva, sweat, and tears for defense?
- lysoszyme
- destroys the cell wall of most bacteria
What is secreted by sweat and tears for defense? (not saliva)
- defensin
- kill bacteria by destroying the cell wall
Hapten
foreign substance so small the immune system doesn’t recognize them as foreign substances
What is the name for a foreign substance so big that it is immediately recognized by the immune system
super-antigen
Phagocytosis
cells engulfing/swallowing/ingesting of bacteria
What are examples of the 2nd line of defense? (4)
- phagocytic WBC
- NK Cells
- Antimicrobial Proteins
- Inflammation
What comprises the 3rd line of defense?
immune system: B/T Cells
What are the functions of NK Cells?
- while kiling foreign substances, they also die (kamikaze cells)
- detect cancer cells early
- first to appear to fight viral cells
What are phagocytic WBCs?
- neutrophils
- eosinophils
- monocytes
- macrophages (transformed from monocytes)
- basophils
Identify APCs
antigen presenting cells
- macrophages
- dendritic cells
What are Antimicrobial Proteins?
proteins molecules that kill microbes
What is the first WBC to appear at an area of tissue damage and bacterial infection?
Neutrophil
What WBC comprises 60 - 70% of total WBCs in the body?
neutrophil
What percentage of total WBC do Eosinophils comprise?
1.5 - 3%
Characteristics of Eosinophils
- limited phagocytic activity
- attracted to sites of parasitic infection
What percentage of total WBCs do Monocytes compose?
3 - 7%
What are macrophages?
What do they do?
- matured monocytes
- have ability to swim in interstitial space looking for hiding microbes
- then attached to microbes and secrete chemicals that will alert immune system to come detroy them
- APCs
What are Dendritic Cells?
- APCs
- have long arms to go in between cells and grab the microbes
What percentage of total WBCs do Basophils comprise?
0.5%
Characteristics of Basophils
- secrete histamine for inflammatory allergy reaction (running nose, red eyes, sneezing…)
- secrete pyrogens
What is a pyrogen?
chemical secreted by basophils that induce a mild fever to stop spread of microbes
What is an example of an anti-pyrogen? (2)
- tylenol
- ibuprofen
What are Complements?
~ 26 - 30 interacting protein molecules found mostly in the serum of animals
- Antimicrobial Proteins
List Examples of Antimicrobial Proteins (3)
- Complement System
- Lymphokines
- Interferon/Interleukin I and II
Lymphokines
- Antimicrobial Proteins
- soluble protein molecules that are produced and secreted by sensitized T lymphocytes
Interferon/Interleukin I and II
- Antimicrobial Proteins
- chemicals secreted to warn neighboring cells that they are infected and what type of infection they have
- they may generally or specifically protect the neighboring cells
What must occur to cells damaged by physical injury?
they must be replenished
What is the body’s response to physical injury?
inflammation
What is diapedesis?
passage of blood cells from capillaries into the tissues
Hemorrhage
results from prolonged diapedesis (internal bleeding)
What are the 4 signs of Inflammation?
And their alternate names
- Heat -> calor
- pain -> dolor
- red -> rubor
- swell -> tumor
What is the antigenic determinant?
AKA
- special part of antigen used to determine the antigen and its shape
- AKA epitope
- anitbodies are then made to combat the antigen
What are antibodies composed of?
- variable regions
- constant regions
- light chains
- heavy chains
What is FAB?
AKA?
- Antigen Binding Fragment
- AKA Paratope
- where antigens bind to the antibodies
What does it mean that the antibody is a dimer?
the antibody can hold the antigen at 2 different spots
What are the 4 characteristics of the immune system?
- specificity
- diversity
- self-nonself recognition
- immunological memory (AKA anamnestic response)
When Ab binds with Ag, what does it create?
Ag-Ab Complex
What are the different types of the Ag-Ab Disposal Systems? (6)
- Agglutination
- Opsonization
- Neutralization
- Complement System
- Naturalization
- Precipitation
How does specificity pertain to the immune system?
immune system will recognize and eliminate a specific microbe
How does diversity pertain to the immune system?
immune system must have the capacity to recognize the numerous types of diverse foreign substances
Self-nonself Recognition
- characteristic of the immune system
- ability of the immune system to distinguish itself from all others
What is Rheumatoid Arthritis?
the immune system fighting itself at the joints
What occurs if the immune system cannot perform self-nonself recognition?
autoimmune disease
What is amnestic response?
- AKA immunological memory
- characteristic of the immune system
- ability of the immune system to remember all previously encountered moluecules so it can know how to fight them again
