Immunity Flashcards
(38 cards)
When self-tissue is perceived as foreign or dangerous it is
auto-immunity
When the response to an invader is excessive it is
allergies, hypersensitivity
What is a microbe
a bacteria, virus
Substance that tends to kill or damage microbes
Antimicrobial substance
Antigen
large molecule that elicit specific responses from hosts
Epitope
a specific discrete component of an antigen that attract immune responses
What two responses does the immune system have
1) Innate
2) Adaptive
General response Rapid, early response always the same primarily reacts to microbes relies on phagocytes and antimicrobials
Innate; first line of defense (we are born with it)
What is the first line of defense
skin and mucous membrane
lysozyme
an enzyme that breaks down the cell wall of some bacteria
What is the second line of defence (internal defences)
consist of antimicrobial substances, and natural killer cells (NK cells) and phagocytes
Specific response
slower, develops in reaction to specific attributes of invader
works with innate processes to enhance reactivity
attacks microbes and antigens
generates immunologic memory - subsequent exposures lead to a more rapid response
Adaptive (develops w/ exposure to organism/substance)
Which response is meant by the term “immune system”
Adaptive response
The primary cells of adaptive immunity are B Lymphocytes (Bcells), and T-lymphocytes (Tcells)
T or F?
True
What two things do lymphocytes do?
1) act as regulator cells, which assist in controlling and orchestration of the immune response
2) act as effector cells by killing/eliminating the microbe or antigen
What are accessory cells?
Phagocytes (macrophages, neutrophils) that kill or break apart an invader. Dendritic cells present antigens/epitopes to killers
Immune cell locations
In the blood and lymph ; high number of immune cells and other immune materials circulating in the blood and lymph
Known as Humoral immunity
Found in tissues and organs
Lymph nodes, spleen, skin, mucosa, vital organs
Key players in humoral immunity
B-cells - Very good at recognizing microbes and antigens
B-cells also produce antibodies
What happens when a b-cell is activated?
it selects the type of clone needed.
when it reaches full maturation it is called a plasma cell
Plasma cells produce and secretes antibodies designed for a specific antigen. Antibodies bind to epitopes and either kill/neutralize the invader, or present them to T-cells or macrophages
Some B-cells are memory cells
T or F?
Memory cells do not participate in the initial immune response. They stay in the body to respond quickly if a secondary exposure to the same antigen occurs
Which is the most abundant type of antibody
IgG
The only antibody to cross the placenta is ___
IgG
Which antibody activates killer cells and the compliment system?
IgG
