Exam 4: Immunology Flashcards
where are all WBC generated?
bone marrow
what are the diffrent kinds of phagocytes?
1) neutrophils
2) monocytes
what is a neutrophil?
important in combating bacterial infection
what is a monocyte?
phagocytosis of blood
what is a macrophage?
monocytes which diapedis into the tissue and differtiante
what are the three diffrent types of lymphocytes?
1) B cells
2) t cells
3) NK cells (natural killers)
what is the function of a B cell?
they contact antigens and develop into plasma cells and secrete anitbodies
where do B cells mature?
in the bone marrow and are sent out to the other lymphoid tissues
what is the function of T cells?
develop into cytotoxic T cells which secrete chemicals to cause lysis of infected cells
where do T cells mature?
thymus gland
what is the function of NK cells?
destory virus by infected cells
what is the first line of defense?
1) the skin, which consists of keratin
2) Mucus membranes
what do the glands in the skin secrete?
sebum (oil) which is bacteriocidal
what is the function of mucus membranes?
very thick and can trap antigens
What is the second line of defense?
nonspecific
1) inflammation
2) interferons
3) complement
what causes inflammation?
caused by tissue injury or microbial invasion
what are the steps of inflammation?
1) macrophages engulf
2) dialation and increased permeability
3) containment of foriegn matter
why do macrophages release cytokines?
to allow other leukocytes to migrate to the injured area
what chemical compound allows for increased permeability?
histamines
what cells release heparin?
mast cells
what is heparin?
an anticoagulant to stimulate BF to the area
what are interferons?
signal
chemicals released from viral infected, T, and NK cells
what is a complement?
a group of inactive proteins made by the liver
how can complements become active?
binding directly to the bacterium or to an antibody bound to bacterium
