opal Flashcards Preview

Dragon > opal > Flashcards

Flashcards in opal Deck (43)
Loading flashcards...
1
Q

all immune cells come from

A

bone marrow

2
Q

B-cells are activated in

A

spleen and lymph nodes

3
Q

T-cells mature in

A

thymus

4
Q

tonsils and adenoids are examples of

A

gut-associated lymphoid tissue

5
Q

leukocytes

A

Cells of the immune system involved in protecting body against infectious disease and foreign invaders.
All white blood cells derived from a multipotent cell in the bone marrow known as a hematopoietic stem cell. Leukocytes are found throughout the body, including the blood and lymphatic system.

6
Q

skin

A

physical barrier and secretes antimicrobial compounds like defensins

7
Q

mucous

A

on mucous membranes traps pathogens; in respiratory system, mucous is propelled upward by cilia and can be swallowed or expelled

8
Q

tears and saliva contain

A

lysozyme, an antibacterial compound

9
Q

defenses of gut

A

stomach produces acid, which kills most pathogens. colonization of gut helps prevent outgrowth by pathogenic bacteria through competition

10
Q

complement system

A

can punch holes in cell walls of bacteria to make them osmotically unstable

11
Q

interferons

A

given off by virally infected cells and help prevent viral replication and dispersion to nearby cells

12
Q

macrophages

A

ingest pathogens and present them on major histocompatibiltiy complex (MHC) molecules. they also secrete cytokines

13
Q

MHC-I

A

present in all nucleated cells. present endogenous antigen (proteins from within the cell) to cytotoxic T-cells (CD8+ cells)

14
Q

MHC-II

A

present in professional antigen-presenting cells (macropahges, dendritic cells, some B-cells, and certain activated epithelial cells) and display exogenous antigen (proteins from outside the cell) to helper T-cells (CD4+ cells)

15
Q

dendritic cells

A

antigen-presenting cells in the skin

16
Q

natural killer cells

A

attack cells not presenting MHC molecules, including virally infected cells and cancer cells

17
Q

granulocytes

A

include neutrophils, eosinophils, basophils

18
Q

neutrophils

A

ingest bacteria, particularly opsonized bacteria (those marked with antibody). they can follow bacteria using chemotaxis.

19
Q

eosinophils

A

used in allergic reactions and invasive parasitic infections. they release histamine, causing an inflammatory response.

20
Q

basophils

A

used in allergic reactions. mast cells are related cells found in the skin

21
Q

humoral immunity

A

centered on antibody production by plasma cells, which are activated B-cells

22
Q

when activated, antigen-binding region undergoes

A

hypermutation to improve specificity of antibody produced. cells may be given signals to switch isotypes of antibody (IgM, IgD, IgG, IgE, IgA)

23
Q

circulating antibodies can

A

opsonize pathogens (mark them for destruction), cause agglutination (clumping) into insoluble complexes that are ingested by phagocytes, or neutralize pathogens

24
Q

cell-surface antibodies

A

can activate immune cells or mediate allergic reactions

25
Q

memory b-cells

A

lie in wait for a second exposure to a pathogen and can then mount a more rapid and vigorous immune response (secondary response)

26
Q

cell-mediated immunity is also called

A

cytotoxic immunity

27
Q

cell-mediated immunity is centered on the functions of

A

T-cells

28
Q

T-cells undergo maturation in

A

the thymus through positive and negative selection. the peptide hormone thymosin promotes T-cell development.

29
Q

positive selection

A

only selecting for T-cells that can react to antigen presented on MHC

30
Q

negative selection

A

causing apoptosis in self-reactive T-cells

31
Q

helper T-cells also called

A

Th or CD4+

32
Q

helper T-cells

A

respond to antigen on MHC-II and coordinate the rest of the immune system, secreting lymphokines to activate various arms of immune defense. Th1 cells secrete interferon gamma, which activates macrophages. Th2 cells activate B-cells, primarily in parasitic infections

33
Q

cytotoxic t-cells also called

A

Tc, CTL, CD8+

34
Q

cytotoxic T-cells

A

respond to antigen on MHC-I and kill virally infected cells

35
Q

suppressor T-cells also called

A

regulatory

36
Q

suppressor T-cells

A

tone down the immune response after an infection and promote self-tolerance

37
Q

memory T-cells

A

serve a similar function to memory B-cells

38
Q

in allergic reaction

A

nonthreatening exposures incite an inflammatory response

39
Q

passive immunity

A

transfer of antibodies

40
Q

active immunity

A

activation of B-cells that produce antibodies to an antigen

41
Q

lymphatic system

A

circulatory system that consists of one-way vessels with intermittent lymph nodes

42
Q

the lymphatic system connects

A

to the cardiovascular system via the thoracic duct in teh posterior chest

43
Q

the lymphatic system accomplishes

A

equalizes fluid distribution, transports fats and fat-soluble compounds in chylomicrons, and provides sites for mounting immune responses