12.1/12.2 Vocab Quiz

lymph

clear, transparent, sometimes faintly yellow fluid collected from tissues and flows in the lymphatic vessels

interstitial fluid

leaked fluid in the spaces between cells

endothelial cells

make up the walls of lymphatic capillaries to allow for fluids to easily enter the lymphatic capillaries, but make it hard to leave

lymphatic vessels

vessels that carry lymph

lymphatic trunks

lymphatic capillaries joined together to form collecting vessels

lymphatic valves

tissue flaps that act as one-way valves inside lymphatic vessels

lymphocytes

WBCs found in large amounts in lymphatic tissues

T lymphocytes (T cells)

mature in thymus

B lymphocytes (B cells)

mature in bone marrow

Natural killer (NK) cells

nonspecific defense cells that recognize and destroy virus-infected cells and cancer cells

macrophages

cells that phagocytize pathogens and old blood platelets

phagocytize

surround and destroy

pathogens

disease causing agents

mucosa-associated lymphatic tissue (MALT)

lymphatic tissue found in mucous membranes that line passageways open to the outside would (include respiratory, gastrointestinal, urinary, and reproductive tracts)

pharyngeal (adenoid) tonsils

lymphatic tissue at the back of the nasopharynx

palatine tonsils

lymphatic tissue found at the back of the mouth on the left and right side (most commonly infected)

lingual tonsils

lymphatic tissue found on either side of the base of the tongue

lymphatic nodules

small localized clusters of dense tissue formed by lymphocytes and macrophages

lymph nodes

small, bean-shaped structures found along the lymphatic vessels throughout the body that cleanse lymph and store and produce T and B cells

spleen

largest lymphatic organ in the body, located in the abdomen below the diaphragm; filters blood and activates an immune response if necessary

phagocytosis

phagocytes engulfing and destroying foreign matter and debris

neutrophils

phagocytize bacteria and cellular debris; most common leukocyte

macrophages

formerly monocytes; phagocytize pathogens in tissues

exocytosis

cells membranes fuse together to push debris from vesicles outside of cell

complement system

the circulation of more than 30 proteins in the blood plasma that work together to destroy foreign substances; complements/balances the specific and nonspecific defense systems

classical pathway

begins when one of the circulating complement proteins, usually inactive, recognizes antibodies bound to a target

complement proteins

proteins in the blood that work with the immune system cells and antibodies to defend the body against infection

alternative pathway

triggered when the C3b complement protein binds to foreign material

opsonins

proteins that make cells more attractive to phagocytes

mast cells

a type of cell found in connective tissue

membrane attack complex (MAC)

complement proteins that insert themselves into the bacterial cell membrane

interferons

proteins released by cells that have been infected with viruses

alpha interferons

produced by virus-infected leukocytes

beta interferons

produced by virus-infected fibroblasts

gamma interferons

produced by NK cells and T cells

prostaglandins

fatty acids involved in controlling inflammation, body temperature, and other chemicals

pyrogens

chemicals that raise the set-point temperature of the neurons in the hypothalamus