lymphoid system 1 Flashcards
1
Q
innate immunity is
A
- immediate
- nonspecific actions
- first course of action
- include physical barriers
- include NKCs
- granulocytes
- leukocytes
- produced in bone marrow
2
Q
physical barriers of innate immunity
A
- skin
- mucous membranes of GI tract
- respiratory
- urogenital tracts
3
Q
natural killer cells (NKC)
A
- destroy various unhealthy host cells
- include virus or bacteria and tumorigenic cells
4
Q
adaptive immunity
A
- acquired gradually by exposure to microorganisms
- aimed at specific microbial invaders
- slower response
- more recently evolved
- B and T lymphocytes
- memory lymphocytes
- produced in bone marrow
5
Q
B and T lymphocyte activation in adaptive immunity
A
- against specific invaders
- specific molecules from antigen presenting cells
6
Q
antigen presenting cells (APCs) are derived from
A
- monocytes
7
Q
the lymphatic system protects against potentially harmful effects of
A
- pathogens
- foreign substances
- infectious agents (bacteria and viruses)
- abnormal cells
- can target tumor cells
8
Q
the major function of the lymphoid system:
A
to serve as a source of immunocompetent cells that can react with and neutralize antigens and to distinguish self from non-self
9
Q
the lymphoid system is comprised of
A
- lymphoid tissues
- organs comprised of lymphocytes and other cells of mononuclear phagocyte system
10
Q
lymphoid tissue is classified as
A
specialized reticular connective tissue
11
Q
arrangement of components of lymphoid system
A
- diffuse subepithelial lymphocyte aggregates
- densely packed
12
Q
densely packed arrangement occurs in:
A
- lymphoid nodules
- are part of MALT
13
Q
mucose associated lymphoid tissues (MALT) includes:
A
- tonsils
- payer patches
- appendix
- GI, respiratory, urinary, and reproductive tracts
14
Q
lymphoid organs can be
A
- unencapsulated
- encapsulated
15
Q
encapsulated organs include
A
- lymph nodes
- thymus
- spleen
16
Q
unencapsulated organs include
A
- bone marrow
17
Q
lymphoid organs can be classified as:
A
- primary
- secondary
18
Q
primary lymphoid organs are
A
major sites of lymphocyte production and maturation
19
Q
primary lymphoid organs include
A
- bone marrow
- thymus
20
Q
what do B cell lymphocytes do?
A
- mediate humoral immunity by giving rise to plasma cells (synthesize antibodies)
- inactivate foreign antigens
21
Q
what do T cell lymphocytes do?
A
- mediate cellular immunity against microorganisms
22
Q
what do secondary lymphoid organs do?
A
- carry out immune response
23
Q
secondary lymphoid organs include:
A
- lymph nodes
- spleen
- MALT
24
Q
lymphoid tissues derive from:
A
mesoderm
- except thymus which derives from mesoderm and endoderm
25
MALT subdivided into
- GALT (gut)
- BALT (bronchus)
- NALT (nasal)
- VALT (vulvovaginal)
26
GALT includes
- tonsils
- Payer patches
- appendix
27
MALT contains
- B cells and T cells
- primarily B cells
- T cells predominate nearby areas
28
lymph nodes
- bean/kidney shaped
- found in lymphatic vessels and lymph
- occur as chains or groups
- in neck, groin, mesenteries, axillae, abdomen
29
lymph nodes derive from
the mesenchyme
30
main function of lymph nodes:
- filtration of lymph before it returns to thoracic duct
- production of lymphocytes that are added to lymph
- synthesis of antibodies (IgG)
- recirculation of lymphocytes
31
structure of lymph nodes:
- paracortex
- cortex
- medulla
32
lymph node flow
1. afferent lymph vessels
2. subcapillary sinus
3. trabeculae sinus
4. paracortex
5. medullary sinus (medullary cord
6. efferent vessel
33
where do lymphocytes enter high endothelial venules?
paracortex
34
high endothelial venules (HEVs) are where...
lymphocytes exit blood and become localized in lymph nodes
35
B cells localize where in the lymph nodes?
cortex
36
where do T cells localize in the lymph nodes?
paracortex
37
where do lymphocytes proliferate?
in germinal center of the spleen
- B lymphocytes remain in the germinal center
38
thymus function
Facilitates the foreign antigen-independent maturation of T lymphocytes
- much larger in children
39
thymus gland
- flat
- bilobed
- in anterior mediastinum
- involuted and parenchyma replaced by adipose connective tissue during puberty***
40
parenchyma of thymus is later...
replaced by adipose in adults
41
where does positive selection occur?
in thymus
42
medulla of thymus contains what?
hassel's corpuscles
43
hassel's corpuscles
- highly active
- produce hormones to help lymphocytes differentiate when located on periphery of thymus
44
the spleen produces:
- lymphocytes and antibodies
- these are delivered directly to the blood not the lymph
45
function of the spleen
- filtration of the blood (only lymphoid organ that does)
- defense against blood-born antigens
- main site of erythrocyte destruction
- produces antibodies and activated lymphocytes
46
splenic pulp components
- white pulp (lymphoid nodules and periarteriolar lymphoid sheaths - PALS)
- red pulp (sinusoids and splenic cords)
47
PALS is primarily made of
T cells
48
the spleen contains:
- lymphoid nodules
- periarteriolar lymphoid sheaths (PALS)
49
are lymphoid nodules in the spleen part of the MALT?
NO
50
comparison of major lymphoid organs
51
lymphatic drainage in teeth
- lymphatic vessels have been identified in vascular endothelial growth factor (VEGF) receptor 3
- located in root pulp
52
macrophages
- located in connective tissue, lymphoid organs, lungs, bone marrow, pleural, and peritoneal cavities
- produces cytokines and inflammation factors, is antigen processing and presenting
53
kupffer cells
macrophages of the liver
54
microglial cells
macrophages of CNS
55
Langerhans cells
antigen processing and presentation in epidermis
56
dendritic cells
antigen processing and presentation in lymph nodes and spleen
