Innate immunity consists of defenses that are _______ active against pathogens, but incapable of _________.
always active, targeting specific invaders
B-cells develop in the _________, but are activated in ______ or _____. Their major function is produce ______. They are part of the s_______, h_________ immune system.
bone barrow
activated in spleen or lymph nodes
antibodies
specific, humoral
T-cells develop in the _______, and mature in the ______. Their main functions are to ________ the immune system and directly __________. They are part of the s ______, c_______ immune system.
bone marrow
thymus
coordinate, kill infected cells
specific, cell-mediated
Granulocytes include n_______, e_________, and b_______. Agranulocytes include l__________ (____________) and m__________(m__________).
Granulocytes include neutrophils, eosinophils, and basophils. Agranulocytes include lymphocytes (B and T-cells) and monocytes (macrophages).
Skin proves a ________ barrier and secretes _______, such as d_______s. L_____e is an enzyme present in tears and saliva. S______ _____d is an antimicrobial mechanism in the digestive system. The normal g______ f________ provides c_____, making it hard for pathogenic bacteria to grow in the gut.
physical, antimicrobial enzymes, defensins
lysozyme
stomach acid
gut flora, competition
C_____t is a set of proteins in the blood that can create h_____s in bacteria.
Complement
holes
Professional antigen-presenting cells include m________s, d_____c c___s in the s____n, some ___ cells, and certain activated e________l cells.
macrophages, dendritic cells, skin, B-cells, epithelial
MHC-I is found in all n______d cells and presents e_______s antigens, which are created ______ the cell. This is good for detection of cells with i________r pathogens, such as v_____s.
nucleated endogenous within intracellular viruses
MHC-II is found in only a______n p______g cells and presents proteins that result from digestion of e______s antigens.
antigen presenting
exogenous
Natural killer cells are activated by cells that do not present _______, such as v______y i________d cells and c______r cells.
MHC
virally infected
cancer
Neutrophils are activated by b_____a, especially those that have been o__________d (t_____d with a______y).
bacteria
opsonized
tagged
antibody
Eosinophils are activated by i_____e p_______s and a_____s.
invasive
pathogens
allergens
Basophils and m____t cells are activated by a____s.
mast
allergens
P___a cells form from b___s exposed to antigen and p_____e a________s. M_____y b_____s are also produced.
plasma
B-cells
produce antibodies
Memory B-cells
Helper T-cells c_______e the i_____e s_______m through l______s. They respond to antigen presented on M____ class___.
coordinate
immune system
lymphokines
MHC-II
Respond to MHC-II
CD4+ (Helper T)
_____ T-cells directly kill infected cells and respond to MHC class ____
cytotoxic (CD8+)
MHC-I
S____r t____s or r______y t_____s quell the ______ after a pathogen ________, and promote s____ t_____.
Supressor T-cells regulatory T-cell immune response has been cleared self-tolerance
Circulating Ab can mark a pathogen for destruction by p_____c cells (o_____n), cause a________n of the pathogen in insoluble complexes that can be taken up by p_______c cells, or n________e the pathogen by preventing its ability to i_____e tissue.
phagocytic opsonization agglutination phagocytic neutralize invade
B-cells originally mature in bone marrow and, at this point, have some s________y. However, antibodies that can respond to a given antigen undergo h__________n. Those B-cells with the highest affinity survive and proliferate, i__________ over time.
specificity
hypermutation
increasing affinity for the antigen
Positive selection occurs when ____cells in the ____s that can respond to antigen presented on MHC survive (those that do not will undergo apoptosis). Negative selection occurs when ____ cells that respond to ________ undergo apoptosis before leaving the ___s.
T- thymus T- self-antigen thymus
Active immunity refers to
inducing body to make Ab
Passive immunity does not involve
stimulation of plasma cells
The structure primarily responsible for returning materials from lymphatic circulation to the cardiovascular system is the t_____ _____t, which returns lymphatic fluid to the ____.
thoracic duct
left subclavian
Gut-associated lymphoid tissue include t___ and a____.
tonsils, adenoids
I______s are given off by virally infected cells and help prevent viral replication and dispersion to nearby cells.
Interferons
Mast cells are fond in the s__n
skin
Humoral immunity is centered on a______y production by p___a cells, which are activated __-cells.
antibody, plasma, B-cells
Memory B-cells wait for a second exposure and mount the s______y response.
secondary
Cell-mediated or c_____c immunity is centered on the function of __-cells.
cytotoxic. T-cells.
Macrophages ingest pathogens and present them on MHC. They also secrete c_____s.
cytokines
Helper T-cells activate various arms of the immune system by secreting l_____s. Th1 secrete i_____n g___a, which activates m_______s. Th2 activate __- cells, primarily in p______c infections.
lymphokines, interferon gamma, macrophages
B
parasitic