Immunity Study Questions Flashcards
what is the main function of the immune system?
protect the body from foreign invaders and prevent disease
what organs are involved in immunity?
spleen, lymph nodes, thymus, galt, bone marrow
how does the lymphatic system protect the body from disease?
it filters lymph to remove potential pathogens before they can enter the circulatory system
where is malt found?
tonsils (pharynx), adenoids (pharynx), peyer’s patches (intestines), and (in rabbits) the appendix (intestines), as well as clusters of lymphoid tissue in the gastrointestinal tract
what is the significance of the thymus?
responsible for maturation of T lymphocytes, which are responsible for cell-mediated immunity
what are the 2 main subcategories of the immune system?
innate and adaptive immunity
how does specific immunity differ from nonspecific immunity?
specific immunity responds to particular antigens in particular ways, whereas nonspecific immunity responds to all antigens and attacks them in the same way
how does adaptive immunity work?
it targets specific organisms, but it is slower to respond to an invading organism, it is not present at birth but develops and adapts as the animal matures and is exposed to a variety of antigens
what is the difference between the first and second lines of defense against invading pathogens?
the first line of defense is composed of external barriers (skin, mucous membranes, secretions); the second line of defense is internal and activated only when the first line of defense fails
the body’s innate defense against viral pathogens is driven by the production of what?
interferons
what are the pros and cons of fever?
benefits of fever include increased rate of phagocytosis, slowed bacterial growth, and potential killing of the pathogen; risks include denaturing of the proteins and injury to bodily tissues and cells
what cell type of innate defense targets tumor cells?
natural killer cells
what types of cell are phagocytic?
neutrophils, eosinophils, monocytes, tissue macrophages; all white blood cells except lymphocytes and basophils are capable of phagocytosis
what are the four cardinal signs of inflammation?
redness, swelling, heat, pain, loss of function
where are b cells produced and where do they mature?
b cells originate in the red bone marrow; b cells mature in the red bone marrow
where are t cells produced and where do they mature?
t cells originate in the red bone marrow and mature in the thymus
which cell produces antibodies?
b lymphocytes that have differentiated into plasma cells
what are the three stages of differentiation of lymphocytes?
- native cells have entered the lymphatic system but have not encountered an antigen
- cytotoxic or effector cells have been activated and are involved in eliminating a pathogen
- memory cells are the survivors of past infections, capable of providing long-term immunity
what are the functions of each of the five immunoglobulins?
IgM: acute infections IgG: chronic infections IgA: mucosal immunity IgE: allergic reactions and parasitic worms IgD: activates basophils and mast cells
what are the three types of t lymphocytes?
- helper t cells (th) secrete cytokines into the surrounding tissue to improve immune response
- cytotoxic t cells (tc) attach to the antigenic cells and destroy them
- regulatory t cells (ts) inhibit helper t cell and cytotoxic t cell function by negative feedback, they also prevent b cells from transforming into plasma cells
how do vaccines protect patients from disease?
vaccines introduce a weakened form of a pathogen to which the animal’s body mounts an immune response in which memory cells are produced; this allows the immune system to respond more quickly and effectively should it encounter the natural form of the pathogen
what kind of immunity do vaccines provide?
active immunity
what three factors influence the ability of a pathogen to cause disease?
- virulence of the pathogen and degree of pathogenicity
- immune system strength
- mode of infection/transmission
what are the three types of resistance that prevent and animal from contracting a disease?
acquired, individual, and species resistance
which type of resistance prevents humans from contracting canine distemper?
species resistance
which hypersensitivity reaction is likely involved in a vaccine reaction?
type 1
what part of the spleen has immunologic functions?
the white pulp which is made of lymphatic tissue
what is the function of galt?
to ensure that pathogens that survive the acidic environment of the stomach can no infect the animal via the gastrointestinal tract
what chemicals are released as a result of the inflammatory response?
histamine, prostaglandins, leukotriens, and cytokines
what are the two types of cell mediated immunity?
active and passive immunity
