lymphatic & immune system key terms

lymph

extracellular body fluid found in lymphatic vessels and nodes

lymphatic capillaries

microscopic vessels of the lymphatic system that are very permeable

lymph nodes

lymphatic system structures that filter unwanted substances such as pathogens and cancer cells from the lymph

macrophages

white blood cells that develop from monocytes to engulf and destroy bacteria and other foreign substances

lymphocytes

white blood cells that monitor body fluids for the presence of antigens; can trigger an immune response

metastasis

when cancer spreads to a new location in the body away from its original site

tonsils

trap pathogens entering the throat

thymus

involved in producing lymphocytes in children

peyer’s patches

capture and destroy bacteria in the small intestine

spleen

filters pathogens and debris from blood

nonspecific defenses

protect the body from all foreign invaders regardless of their

type or location

specific defenses

produce specially formulated substances to attack specific

antigens to which the body has been previously exposed

mechanical barriers

examples include the skin and mucous membranes which form

physical barriers to pathogens

phagocytic cells

specialized white blood cells such as macrophages and

neutrophils that engulf and destroy foreign particles and

destroy them

natural killer cells

type of lymphocyte that binds to tumor cells and virus-infected

cells by injecting special proteins that create holes in the

plasma membrane

inflammatory response

triggered by an injury to body tissues; damaged cells release

inflammatory chemicals such as histamine and kinins (redness,

heat, swelling, pain, loss of function)

chemotaxis

movement of cells towards or away from a chemical stimulus

diapedesis

the movement of white blood cells through capillary walls into

tissues

complement proteins

group of plasma proteins that attach to foreign cells and

destroy them or tag them for destruction

interferons

small proteins secreted by virus-infected cells that protect

other cells nearby from being infected

fever

abnormally high body temperature; response to invading

microbe

antigens

foreign invaders that trigger an immune response

humoral

employs antibodies in body fluids; also called

antibody-mediated immunity

cellular

type of immunity that uses living cells (lymphocytes) to destroy

infected cells directly or indirectly

antibodies

specialized proteins produced in response to antigens

B cells

produce antibodies, part of humoral immunity, develop in

bone marrow

T cells

do not produce antibodies, part of cell-mediated immunity,

develop in the thymus gland

clonal selection

rapid production of B cell clones that occurs during humoral

response

plasma cells

type of B cell clone that produces antibodies

memory B cells

type of B cell clone that remains in the body to fight second

exposure to the antigen

secondary humoral response

swift effective response by memory B cells to second exposure

active immunity

acquired during an infection or vaccination; provides immunological memory

passive immunity

acquired from mother's or donor's antibodies; no immunological memory

vaccines

lab-created preparations containing weakened, dead, or partial microbes that stimulate a primary immune response when introduced to the body

immunoglobulins

another word for antibodies

monoclonal antibodies

lab-produced molecules that act as antibodies that bind to only

one substance; used for diagnostic and treatment purposes

cellular immune response

occurs when body cells that contain antigens are destroyed; depends on macrophages and several types of T cells

cytotoxic T cells

type of T cell clone that directly attacks infected cells and

cancer cells

helper T cells

type of T cell clone that circulates through the body stimulating other immune cells into action

allergies

an abnormal immune response to a harmless substance

mast cells

releases histamine and other substances during inflammatory and allergic reactions

anaphylaxis

rare, acute, and systemic allergic reaction that can be life-threatening

immunodeficiency

congenital or acquired deficiency in the number or function of

immune cells or complement

AIDS (acquired immune deficiency syndrome)

syndrome caused by the HIV virus which interferes with the

activity of helper T cells; acquired immune deficiency

syndrome

autoimmune diseases

a variety of diseases caused by the immune system's attacks on

"self" antigens