Lymph_Histology

Question 1

encapsulated lymphoid tissues

Answer 1

thymus, tonsils, lymph nodes, and spleen

Question 2

reticular cells

Answer 2

synthesize reticular fibers…type III collagen that makes supporting framework of lymphoid organs

can be phagocytic

Question 3

diffuse lymphoid tissue

Answer 3

lymphoid tissue that is spread out or not encapsuled

GALT/BALT

Peyers patches

Question 4

peyers patches location

Answer 4

usually in the ileum

Question 5

primary lymphoid nodules

Answer 5

no germinal center, mainly resting B cells and dendritic/macros/reticulars

Question 6

secondary lymphoid nodules

Answer 6

made in response to an antigenic challenge

have germinal center, that is core of resting B cells

mantle or periphery is darker and has plasma cells, resting B cells, memory B cells, dendritic, macro and reticular

Question 7

lymph nodes functions

Answer 7

maintains and produces B and T cells by clonal expansion

primary location for filtration of lymph

Question 8

lymph node structures

Answer 8

encapsulates, cortex/medulla, lymphoid nodules, and a hilum

Question 9

hilum of lymph nodes

Answer 9

region where blood vessels can enter and leave, arterial and venous blood entering and leaving respectively

also has efferent lymphatic vessel for the lymph to leave

Question 10

lymph node cortex

Answer 10

lymphoid nodules, subscapular and cortical sinuses (sinusoids)

Question 11

cells in lymphoid nodules

Answer 11

mainly B cells

Question 12

paracortex of lymph node

Answer 12

mainly T cells that enter in paracortex via high endothelial venules

known as thymus dependent area

Question 13

contents of medulla of lymph node

Answer 13

medullary sinuses and cords

Question 14

high endothelial venules

Answer 14

postcapillary venule…made by a simple cuboidal epithelium

where most of lymphocytes leave blood stream and enter the lymph node via diepadesis

typically found in the paracortex of lymph nodes

Question 15

medullary sinus

Answer 15

endothelium lined spaces, receive lymph from the cortical sinuses

contain macrophages

Question 16

medullary cords

Answer 16

have lymphocytes and plasma cells

Question 17

thymus function

Answer 17

maintains T cells, helps T cells mature

Question 18

thymus structure

Answer 18

encapsulated, has cortex and medulla

Question 19

epithelial reticular cells of thymus

Answer 19

pale cell that surrounds and extends the outer layer of the thymus… form meshwork within which T cells are tightly packed

synthesize many hormones for making T cells immunocompetent

Question 20

thymocytes in the thymus

Answer 20

respond to cytokines and become T cells, migrate from cortex to medulla as they mature

surviving T cells are naive and leave thymus to go to secondary lymphoid tissue

Question 21

blood thymus barrier

Answer 21

within the thymus cortex

makes immunologically protected region ensuring antigens in blood cannot reach the developing T cells in the cortex of the thymus

Question 22

components of the blood thymus barrier

Answer 22

capillary endothelium and basal lamina
perivascular connective tissue (macrophages)
thymic epithelial reticular cells and basal lamina

Question 23

medulla of thymus

Answer 23

have the mature T cells that are loosely packed so lighter stained

contains the Hassal Corpuscles

Question 24

Hassal corpuscles

Answer 24

in thymus medulla, whorl like accretions of epithelial reticular cells

keratinized, increase in number with age

Question 25

spleen functions

Answer 25

maintains and produces B and T cells through clonal expansion

filters blood

stores RBCs and kills bad ones

prenatla hematopoeisis

Question 26

structure of spleen

Answer 26

encapsulated with hilum and lymphoid nodules

no cortex or medulla

Question 27

White pulp nodules in spleen

Answer 27

collections of B cells in the spleen

Question 28

periarterial lymphatic sheaths

Answer 28

collections of T cells in the white pulp of the spleen

Question 29

red pulp of spleen

Answer 29

interconnected network of sinusoids and splenic cords

Question 30

blood flow route in the spleen

Answer 30

splenic artery to trabecular artery to central artert to pnicillar artery to eithe splenic sinusoids of splenic cords

Question 31

central artery of spleen

Answer 31

artery that runs right through the white pulp of the spleen

Question 32

penicillar artery of spleen

Answer 32

artery that takes blood from white pulp and into the red pulp of the spleen

Question 33

sinusoids of the spleen

Answer 33

lined by specialized fusiform epithelial called stave cells

is closed circulation

Question 34

splenic cords of the spleen

Answer 34

loose connective tissue with plasma, reticular, blood and macrophage cells

open circulation

Question 35

marginal zone of spleen

Answer 35

where the blood first enters the spleen, space between white and red pulp

has lots of APCs and macrophages

location where T and B cells are sorted into correct spot

Question 36

tonsil function

Answer 36

maintain and produce B cells

combat antigens entering via nose or oral epithelia

Question 37

tonsil types

Answer 37

pharygeal, palatine, and lingual tonsils

Question 38

tonsil structure

Answer 38

encapsulated with lymphoid nodules

no cortex/medulla and no hilum