Exam #3: Lymphatic Tissue & Organs

Question 1

What are the 2 zones of a secondary lymphatic nodule?

Answer 1

1) Mantle Zone, which is dark staining & contains small mature lymphocytes
2) Germinal Zone, which is light staining & contains medium to large size & immature lymphocytes

Question 2

Solitary Lymphatic Nodule

Answer 2

Temporary

Question 3

Aggregate Lymphatic Nodule

Answer 3

Permanent

Question 4

Where are aggregates of lymphatic nodules located?

Answer 4

• Lymph nodules (tonsils, spleen, & lymph nodes)
• Peyer’s Patches
• Appendix
• BALT

Question 5

What are tonsils?

Answer 5

Aggregates of lymphatic nodules that contain B-lymphocytes

Question 6

Pharyngeal Tonsils

Answer 6

Respiratory/ Pseudostratified Columnar Epithelium with cilia

Question 7

Palatine Tonsils

Answer 7

Nonkeratinized stratified squamous epithelium

Question 8

Lingual Tonsils

Answer 8

Nonkeratinized stratified squamous epithelium

Question 9

Cell types associated with reticular fibers

Answer 9

• Dendritic cells (APC)
• Macrophages (phagocytic)
• Follicular Dendritic Cells (bind antigen/antibody complexes)

Question 10

Cortex of a lymph node

Answer 10

B-lymphocytes

Question 11

Deep Cortex of a lymph node

Answer 11

• T-lymphocytes

- HEV

Question 12

Medulla of a lymph node

Answer 12

Medullary cords

Question 13

How does the thymus differ from lymph nodes?

Answer 13

• No afferent lymphatic vessels
• No 3D reticular network
• No lymphatic nodules
• No B-lymphocytes
• No sinuses

Question 14

Type I epitheloreticular cells

Answer 14

• Form a seal around the cortex of the thymus, separating it from the CT capsule & trabeculae
• Contain occludens junctions

Question 15

Type II epitheloreticular cells

Answer 15

• Form a meshwork in the midcortex
• Contain desmosomes
• Involved in thymic eduction

Question 16

Type III epithelioreticular cells

Answer 16

• Deep cortex
• Occulens junctions
• Form a seal between the cortex & the medulla

Question 17

Type IV epithelioreticular cells

Answer 17

• Associated with Type III cells & participate in establishment of the barrier at the corticomedullary junction

Question 18

Type V epithelioreticular cells

Answer 18

• Form the meshwork of the medulla

Question 19

Type VI epithelioreticular cells

Answer 19

• Hassall’s Corpuscles

- Contain mature T-lymphocytes

Question 20

Layers of the blood thymus barrier

Answer 20

1) Endothelium
2) Basal Lamina
3) Macrophages
4) Type I epithelioreticular cells

Question 21

DiGeorge Syndrome

Answer 21

• Individuals cannot produce T-lymphocytes
• Lack “cell-mediated” immunity
  (Also, do not have parathyroid glands & may die from tetany)

Question 22

PALS

Answer 22

• Periarterial lymphatic sheath (PALS)

- Tunica adventitia of trabecular arteries infiltrated with T-lymphocytes

Question 23

Splenic Circulation

Answer 23

1) Splenic artery
2) Trabecular artery
3) Central artery w/ PALS (tunica adventitia w/ T-lymphocytes)
4) Penicillar arteries (no PALS)
5) Arterial capillaries
6) Splenic sinuses
7) General circulation

Question 24

White Pulp

Answer 24

• Stains blue with hematoxylin
• PALS (T-lymphocytes)
• Splenic Nodules (B-lymphocytes)

Question 25

Red Pulp

Answer 25

• Stains red with eosin
• Splenic Cords- Filter blood
• Splenic Sinuses