Lymphoid Tissue - Dennis Flashcards Preview

HDM - Midterm > Lymphoid Tissue - Dennis > Flashcards

Flashcards in Lymphoid Tissue - Dennis Deck (49):
1

Where would you find a high concentration of lymphocytes? 2

Lymphoid organs

2

What are the primary lymphoid organs? 3

Thymus

Red bone marrow

3

What is the role of primary lymphoid organs? 3

To PRODUCE the lymphocytes

4

What is the role of secondary lymphoid organs? 4

To ACTIVATE lymphocytes in response to antigens

5

Slide 5

What to do with yellow box

6

Where is simple columnar epithelium found? 6

GI Tract

Genitourinary tract

Respiratory passages

7

What accessory accompanies the simple columnar epithelium of the GI tract?

Villi for absorption

8

What differentiates a primary nodule from a secondary nodule? 9

Secondary nodules (follicles) contain a germinal center along with a mantle and are considered activated primary nodules

9

What is contained within the mantle zone of a secondary follicle? 9

Smaller lymphocytes

10

Within in a secondary nodule where will you find T and B cells? 11

B cells - germinal center > mantle

T cells - localized to the mantle

11

Where would you find non-encapsulated lymphoid tissue? 12

Posterior oral cavity

Oropharynx

Nasopharynx

12

What kind of tissue constitutes the palatine tonsil? 13

Stratified Squamos epithelium

13

What is the role of tonsillar crypts? Where would you find them? 13

Evaginations that increase surface area for capturing and eliminating pathogens

Found within the palatine tonsils

14

Where do you find the pharyngeal tonsil and what does it lack? 15

Posterior wall of the nasopharynx

Does not contain crypts

15

What kind of epithelium makes up the pharyngeal tonsil? 15

Pseudostratified columnar ciliated epithelium

16

Where is the lingual tonsil found and what does it lack that is different from all other tonsils? 15

Along base of tongue

Lacks a capsule

17

What kind of epithelium makes-up the Lingual Tonsil? 15

Stratified squamous epithelium

18

What is MALT? Where is it found? 16

Mucosa-associated lymphoid tissue

GI tract - GALT

Respiratory airways - BALT

Urinary tract

19

What kind of epithelium is found in the stomach?

Stratified Squamos epithelium

20

What kind of lymphoid tissue is concentrated in small intestines specifically the ileum? 17

Peyer Patches

21

Are peyer patches deep or superficial to the gut tract? 18

They are superficial and visible from the lumen of the gut tract

22

What is contained within the veriform appendix? 19

Crypts (maybe just lumen) containing a high number of lymphoid tissue

- no capsule
- no villi

23

What kind of tissue is found within the veriform appendix?

Simple columnar epithelium w/ goblet cells

24

Where is the thymus located? Describe its structure. 23

Belobed structure in the mediastinum lying on the heart

25

What happens with the Thymus over time? 23

Thymus activity decreases due to decreased immature lymphocytes and becomes filled with adipose tissue

26

What three cell types are contained within the cortex of the thymus? 26

T Lymphoblasts (thymocytes)

Macrophages

Thymic epithelial cells (TECs)

27

What are the two components of the cortex of the thymus? 27

Subscapsular (squamous)

Cortical (stellate)

28

What is the role of the cortical (stellate) TEC's of the Thymus? 27

Secrete cytokines for T cell development

Produces keratin and desmosomes

29

What is the role of the Subscapsular (squamous) TEC's of the Thymus? 27

Forms the cortical compartment

Separates the cortex from the medulla

30

What forms the blood-thymus barrier? 28

TEC's

Basal lamina

Endothelial cells

31

What is contained with the Thymic Medulla? 29

Mature T cells coming from the cortex

32

What is the function of the Hassall's corpuscles

Secrete cytokines to aid in maturation of T cells

33

What cells do you find in the Cortex of the Thymus? 31

T cells (T-lymphoblasts)

Subscapsular TEC's (thymic epithelial cell)

Cortical TEC's (thymic epithelial cell)

Macrophages

34

What cells are contained within the Medulla of the Thymus? 31

T cells (mature)

Medullary TEC's (thymic epithelial cells)

Hassall's Corpuscles

Dendritic cells

Macrophages

35

What are the major roles of the spleen? 32

Initiates immune response to blood antigens

Reservoir for platelets

Recycles erythrocytes

Hematopoiesis (early in process)

36

What artery/vein supplies the spleen? 33

Splenic artery & vein

37

What four characteristics define the structure of the spleen? 33

Connective tissue capsule

Trabeculae

White pulp --> lymphoid tissue

Red pulp --> RBC's

38

What is contained within the White pulp of the spleen? 34

T cells

B cells

Macrophages

39

What is contained within the red pulp of the spleen? 34

Erythrocytes

Platelets

Macrophages

Plasma cells

40

What zones are contained within the white pulp of the spleen? 35

Corona (mantle zone - MnZ): small lymphocytes surrounds GC

Marginal Zone (MgZ): transition zone of red and white pulp

41

What is the function of the splenic sinusoids and splenic cords within the red pulp of the spleen? 36, 37

Splenic cords are rich in lymphocytes and macrophages

Blood enter splenic sinusoids where it collects and is cleaned or recycled

42

What is the role of starve cells lining the sinusoids of the red pulp of the spleen? 37

Separate healthy vs unhealthy RBCs (based on elasticity)

43

Describe the vasculature leading to and away from the spleen. 39, 40

Celiac trunk --> splenic artery --> trabecular arteries --> central arteriole --> white pulp --> penicillin arteries --> splenic sinuses --> splenic cords

44

What supplies the splenic sinuses and cords? 40

The penicillar arterioles

45

Within a lymph node what is the area between the cortex and medulla? 43

Paracortex

46

What is contained within the outer cortex of a lymph node? 43

Lymphatic nodule

Germinal Center

Mantle zone

47

What facilitates movement of lymphocytes (T cells) into the lymphoid tissue from the blood? 47

High Endothelial Venule (HEVs)

48

What is the role of the medullary cords? 47

A mass of lymphoid tissue extending from the paracortex

Contains T & B (plasma) cells

49

What separates the medullary cords, what cells does it contain? 48

Medullary sinuses

Contains - macrophages and neutrophils