Lymphatic System

Question 1

Function of lymphatic system

Answer 1

Secondary defense system

Question 2

Methods of defense

Answer 2

1. Humoral immune system
2. Cell-mediated immune system
3. Filtration of lymph and blood

Question 3

Primary method of defense

Answer 3

Epithelial cells

Question 4

Primary defense aka?

Answer 4

Innate / non-specific

Question 5

Secondary defense aka?

Answer 5

Immune / acquired / specific

Question 6

2 types of secondary defense

Answer 6

1. Humoral

2. Cell mediated

Question 7

Cytokines are?

Answer 7

Chemical messengers

Question 8

3 cells/molecules involved in humoral defense

Answer 8

1. B lymphocytes
2. Antibodies
3. Plasma cels

Question 9

2 cells/molecules involved in cell-mediated defense

Answer 9

1. T lymphocytes

2. Cytokines

Question 10

2 classifications of lymphatic tissue

Answer 10

1. Diffuse

2. Dense

Question 11

Diffuse lymphatic tissue is found in?

Answer 11

1. Respiratory tract

2. Lamina propria of GI tract

Question 12

Diffuse lymphatic tissue

Answer 12

Loosely scattered lymphocytes beneath epithelial layers

Question 13

Dense lymphatic tissue

Answer 13

More compact, spherical structures (nodules/follicles)

Question 14

Dense lyphatic tissue is found in?

Answer 14

Submucoa of GI tract

Question 15

What are aggregated lymph nodules?

Answer 15

Accumulations of many nodules

Question 16

Example of aggregated lymph nodules

Answer 16

Peyer’s patches

Question 17

Peyer’s patches are found in?

Answer 17

Wall of intestines, especially ileum

Question 18

What are tonsils?

Answer 18

Areas where lymphoid tissue is very closely associated with epithelium

Question 19

How do you recognize a tonsil?

Answer 19

Lymphocytes invade epithelium

Question 20

What are crypts?

Answer 20

Deep invaginations of epithelium

Question 21

Crypts are found in what type of lymphatic tissue?

Answer 21

Tonsils

Question 22

Crypts are found in the palatine tonsils of all species except?

Answer 22

Carnivores

Question 23

Difference between lymphatic tissue and lymphatic organs?

Answer 23

Lymphatic organs have CT capsule, lymphatic tissue does not

Question 24

Lymph nodes are usually shaped how?

Answer 24

Bean-shaped with hilus

Question 25

Lymphocenter

Answer 25

Constant locations of lymph nodes

Question 26

Lymph node structure

Answer 26

1. Capsule 2. Stroma 3. Cortex 4. Paracortex 5. Medulla 5. Lymph flow

Question 27

Capsule of lymph node

Answer 27

Surrounds node

Question 28

Parenchyma is the?

Answer 28

Functional part of an organ

Question 29

Stroma of lymph nodes

Answer 29

Trabeculae from capsule divide parenchyma into smaller compartments

Question 30

Stroma contains a network of?

Answer 30

Reticular fibers

Question 31

Reticular fibers are type ___ collagen

Answer 31

Type III

Question 32

Cortex is the?

Answer 32

Outer region of parenchyma

Question 33

Species in which cortex is not the outer region of parenchyma

Answer 33

Swine and elephants

Question 34

Cortex contains?

Answer 34

1. Lymph nodules/follicles | 2. Lymph sinuses

Question 35

Appearance of primary lymph nodules

Answer 35

Homogenous

Question 36

2 types of lymph nodules

Answer 36

1. Primary | 2. Secondary

Question 37

Which type of lymph nodules contains a germinal center?

Answer 37

Secondary

Question 38

What is a germinal center?

Answer 38

A lighter center of a lymph nodules which indicates previous antigenic exposure

Question 39

Why do germinal centers have lighter center?

Answer 39

Presence of activated lymphocytes (which ave more vesicular nucleus and more cytoplasm → pale)

Question 40

2 possible fates of activated lymphocytes in germinal center

Answer 40

1. Become plasma cells and secrete antibodies | 2. Become memory cells

Question 41

2 types of lymph sinuses

Answer 41

1. Subcapsular | 2. Trabecular

Question 42

Paracortex is?

Answer 42

Poorly defined zone in deep center next to medulla

Question 43

Paracortex contains mostly?

Answer 43

T lymphocytes

Question 44

Thymus dependent zone refers to?

Answer 44

Paracortex

Question 45

T lymphocytes are produced in?

Answer 45

Thymus

Question 46

How do T cells enter paracortex?

Answer 46

Via HEVs

Question 47

HEV stands for?

Answer 47

High endothelial venules

Question 48

What are HEVs?

Answer 48

Small vessels with unusually tall endothelium

Question 49

Lymph arrives via what type of vessels?

Answer 49

Afferent vessels

Question 50

Medulla is the?

Answer 50

Inner region of lymph node

Question 51

Medulla contains?

Answer 51

1. Medullary cords 2. Medullary sinuses 3. Trabeculae (from cortex)

Question 52

Lymphatic tissue in medulla is in the form of?

Answer 52

Medullary cords

Question 53

Medullary cords contain?

Answer 53

1. Lymphocytes 2. Plasma cells 3. Macrophages 4. Reticular cells

Question 54

What are medullary sinuses?

Answer 54

Lymph sinuses along medullary cords

Question 55

Afferent vessels enter capsule where?

Answer 55

Convex surface of node

Question 56

Afferent vessels drain into?

Answer 56

Subscapular and trabecular sinuses

Question 57

Lymph flow

Answer 57

Percolates through cortical sinuses into medullary sinuses

Question 58

Where are lymphocytes added to lymph?

Answer 58

Medullary sinuses

Question 59

How does lymph penetrate cortex and medulla?

Answer 59

Leaks from sinuses

Question 60

Efferent vessels leave organ where?

Answer 60

Hilus

Question 61

Blood vessels enter and depart where?

Answer 61

Hilus