Immune System Flashcards
What are the functions of the Immune system?
Offers protection from:
Pathogens
Allergens
Foreign substances
Cancer
What is an antigen?
A protein marker that identifies every substance
Every substance (pee venom, pollen etc) carries a protein called antigen and when we injest it our body doesn’t recognize it and will attack
Antigens in our body recognize (like a name tag) our cells and they “belong” so the immune system should NOT attack
A protein marker that identifies every substance
Every substance (pee venom, pollen etc) carries a protein called antigen and when we injest it our body doesn’t recognize it and will attack
Antigens in our body recognize (like a name tag) our cells and they “belong” so the immune system should NOT attack
What is an allergen?
Antigens that cause the allergic response
Bee venom
Pollen
What are types of Immunity?
Non Specific-defense mechanism ( sneeze, cough, tears)
Inflammation
Inherited
Acquired (chickenpox)
Active (when your immune system becomes activated)
Passive (when you receive antibodies)
What is non specific immunity?
Innate
Does not involve memory or prior exposure
Two lines of defense:
First Line-
mechanical and chemical barriers
Reflexes (coughing, sneezing)
Second Line:
Phagocytosis
Inflammation
Fever
Interferons
Complement proteins
Natural killer cells
What are some examples of first line of defense? (No immunity involved, it’s your body’s reaction)
Barriers:
Skin
Mucous membranes
Sweat glands
Stomach acid
Cilia
Reflexes:
Sneeze
Cough
Vomiting
Diarrhea
Examples of second line of defense?
Phagocytosis: (a process by which cells engulf and digest foreign particles)
Neutrophils (wbc)
Monocytes (immature macrophages) and macrophages
Inflammation:
Response to any type of irritant (burn, paper cut etc)
Histamine and other chemicals released
Results in redness, swelling and pain
Examples of second line of defense
Fever:
Caused by release of pyrogens
Stimulates phagocytosis and reduces pathogen reproduction
38.5 degrees and higher is when you need to reduce the fever (Tylenol)
Protective proteins and NK cells:
Interferons protect from viruses (like security guards looking for a virus)
Complement proteins result in cell “lysis” (poke holes in cell wall of offending organism, resulting in bacteria leaking out and it can’t reproduce)
What is the Third line of defense?
Specific immunity or response
Have a different immune system from one country to another
Involves memory (if you’ve encountered an antigen once, you’re body will remember and be ready)
Only have antibodies from the specific antigens that you have encountered in your life
B and T lymphocytes made from stem cells in the bone marrow and work together
T cells travel from the marrow to the thymus gland and mature
B start from stem cells and stay there (B cells = bone)
What is inherited immunity?
Inborn
Innate
Species specific
What is Acquired Immunity?
Picked up during lifetime
Natural (from getting a disease like chickenpox or breastfeeding)
Artificial (vaccine or immune globulin) something you have to seek out **
What is natural active immunity?
The immune system has to get to work to form antibodies (chicken pox)
What is natural passive immunity?
Antibodies are given to an individual without their own immune system having to go to work (mom giving antibodies to baby in utero)
What is the Immune Response?
Antigen is a protein found in many surfaces including our own cells
Those that are “ours” are considered safe
Those that are not ours are considered “unsafe”
Those that are foreign prompt the development of T and B cells (antibodies)
What re T cells?
Come from stem cells in bone marrow
Travels to the Thymus (T) for development and maturation
Some move on to live in tissue and others circulate in blood
Attack antigens directly
What are the steps in T cell activation?
T cells are VERY IMPORTANT
Stem cell in bone marrow then travels to thymus, tissue and blood
An antigen is “presented “ to a T cells travel by a macrophage
T cell activation- antigen binds to receptors on both the T helper call and the T cytotoxic cell and is destroyed
Clone production (once activated, T cells produce clones so an “army” is ready next time) ie) memory and specificity)
What are the T cell subtypes?
1) Killer T cell (kills antigens)
2) Helper T cell ( “BOSSo”- stimulates T and B cells)
3) suppressor T cell (inhibits T and B cells)
4) Memory T cell (remembers antigens for the future- has a “camera”)
What are B cells? (2 types)
Come from stem cells in the bone marrow
Mature in bone marrow and then move to lymphatic tissue and circulate
Interact with antigen indirectly (need “permission”)
