Secondary lymphoid structures

Question 1

Describe the function of secondary lymphoid structures.

Answer 1

Secondary lymphoid structures do not form lymphocytes but house them and other immune cells, serving as sites for immune response initiation.

Question 2

List the types of secondary lymphoid structures.

Answer 2

Secondary lymphoid structures include lymph nodes, spleen, tonsils, lymphatic nodules, and mucosa-associated lymphoid tissue (MALT).

Question 3

Explain the organization of secondary lymphoid structures.

Answer 3

Secondary lymphoid structures are organized into lymphoid organs and aggregates of lymphoid nodules, housed within a reticular connective tissue matrix.

Question 4

How do lymph nodes filter lymph?

Answer 4

Lymph nodes filter lymph by removing unwanted substances as lymph flows through them.

Question 5

Define the components of a lymph node.

Answer 5

A lymph node consists of afferent lymphatic vessels, an efferent vessel at the hilum, a dense connective tissue capsule, trabeculae, an outer cortex, and an inner medulla.

Question 6

What is the role of the outer cortex in a lymph node?

Answer 6

The outer cortex contains lymphoid nodules supported by reticular fibers, housing proliferating B lymphocytes and some macrophages.

Question 7

Describe the structure and function of the medulla in a lymph node.

Answer 7

The medulla contains medullary cords made of connective tissue fibers that support B-lymphocytes, T-lymphocytes, and macrophages, along with medullary sinuses lined with macrophages.

Question 8

How does lymph flow through a lymph node?

Answer 8

Lymph enters through several afferent vessels, creating pressure that pushes it through the node to a single exit vessel, where it is monitored for foreign material.

Question 9

Identify the specific lymph nodes and their drainage areas.

Answer 9

Cervical lymph nodes receive lymph from the head and neck, axillary lymph nodes from the breast, axilla, and upper limb, and inguinal lymph nodes from the lower limb and pelvis.

Question 10

Explain the significance of the germinal center in lymph nodes.

Answer 10

The germinal center within lymphoid nodules is where B lymphocytes proliferate, supported by reticular fibers.

Question 11

What types of cells are found in the mantle zone surrounding the germinal center?

Answer 11

The mantle zone contains T-lymphocytes, macrophages, and dendritic cells.

Question 12

Describe the role of macrophages in lymph nodes.

Answer 12

Macrophages in lymph nodes line the cortical sinuses and medullary sinuses, removing foreign debris from lymph and monitoring for the presence of foreign material.

Question 13

Describe the role of lymphocytes in the immune response.

Answer 13

Lymphocytes initiate the immune response and proliferate, especially in germinal centers.

Question 14

Explain the significance of enlarged lymph nodes.

Answer 14

Enlarged lymph nodes can be palpated in the neck and axilla, indicating potential immune activity or malignancy.

Question 15

How does lymph exit a lymph node?

Answer 15

Lymph exits a lymph node through the efferent vessel.

Question 16

Define malignant neoplasm in the context of lymphoid structures.

Answer 16

A malignant neoplasm from lymphoid structures can present as a nontender, enlarged lymph node.

Question 17

What are common symptoms associated with lymphoma?

Answer 17

Possible symptoms include night sweats, fever, and weight loss.

Question 18

How can Hodgkin lymphoma be treated if caught early?

Answer 18

It can be cured by excision, radiation, and chemotherapy.

Question 19

Identify the age groups most affected by Hodgkin lymphoma.

Answer 19

Hodgkin lymphoma primarily affects young adults and individuals over 60.

Question 20

Differentiate between Hodgkin lymphoma and Non-Hodgkin lymphoma.

Answer 20

Non-Hodgkin lymphoma is more common, with some types being aggressive and others slow-growing.

Question 21

Describe the location and function of the spleen.

Answer 21

The spleen is the largest lymphoid organ located in the left upper abdominal quadrant, filtering and monitoring blood.

Question 22

What is the hilum of the spleen?

Answer 22

The hilum is the indentation where blood vessels and nerves enter the spleen.

Question 23

Explain the blood supply to and drainage from the spleen.

Answer 23

The splenic artery supplies blood to the spleen, while the splenic vein drains it.

Question 24

What is the structure surrounding the spleen?

Answer 24

The spleen is surrounded by a connective tissue capsule.

Question 25

What is found in the white pulp of the spleen?

Answer 25

The white pulp contains clusters of T- and B-lymphocytes and macrophages around the central artery.

Question 25

Define the components of the spleen's internal structure.

Answer 25

Trabeculae from the capsule extend into the spleen, dividing it into red and white pulp.

Question 26

Describe the contents of the red pulp in the spleen.

Answer 26

The red pulp contains erythrocytes, platelets, macrophages, and B-lymphocytes.

Question 27

What are splenic cords and sinusoids?

Answer 27

Splenic cords are made of cells and reticular connective tissue in red pulp, while splenic sinusoids are very permeable capillaries.

Question 28

What is the function of the spleen in relation to blood?

Answer 28

The spleen filters and monitors blood, not lymph, for foreign materials and bacteria.

Question 29

How do macrophages in the spleen contribute to immune function?

Answer 29

Macrophages in the sinusoids of red pulp remove particles by phagocytizing bacteria, debris, and defective erythrocytes and platelets.

Question 30

Outline the path of blood flow through the spleen.

Answer 30

The path of flow is: splenic artery, central artery, sinusoids, venules, and splenic vein.

Question 31

Summarize the functions of the spleen.

Answer 31

The spleen eats foreign particles, clears defective erythrocytes and platelets, and stores erythrocytes and platelets.

Question 32

What role does the spleen play during the first five months of fetal life?

Answer 32

In the first five months of fetal life, the spleen makes blood cells.

Question 33

List reasons for surgical removal of the spleen.

Answer 33

Surgical removal may be performed due to a ruptured spleen, infection, cyst, tumor, lymphoma, or blood disorders.

Question 34

What are the potential risks after spleen removal?

Answer 34

Individuals may be more prone to life-threatening infections after spleen removal.

Question 35

Describe the location and function of the pharyngeal tonsil.

Answer 35

The pharyngeal tonsil is located in the nasopharynx and is called adenoids when enlarged. It plays a role in immune surveillance of inhaled substances.

Question 36

Explain the characteristics of palatine tonsils.

Answer 36

Palatine tonsils are located in the posterolateral oral cavity and are the most commonly affected during acute tonsillitis.

Question 37

How do lingual tonsils differ from other tonsils in terms of location?

Answer 37

Lingual tonsils are located along the posterior one-third of the tongue, distinguishing them from the pharyngeal and palatine tonsils.

Question 38

Define acute tonsillitis and its common symptoms.

Answer 38

Acute tonsillitis is the inflammation and infection of the tonsils, commonly presenting with symptoms such as fever, chills, sore throat, and difficulty swallowing.

Question 39

What are tonsillar crypts and their significance?

Answer 39

Tonsillar crypts are invaginations in the tonsils that trap material and contain lymphoid nodules, contributing to immune function.

Question 40

Explain the role of lymphoid nodules in the immune system.

Answer 40

Lymphoid nodules are clusters of lymphoid cells that help defend against infection and are found in various body organs.

Question 41

Describe the structure and function of MALT.

Answer 41

MALT, or mucosa-associated lymphoid tissue, is located in the gastrointestinal, respiratory, genital, and urinary tracts, helping to defend against foreign substances.

Question 42

How do Peyer patches contribute to the immune system?

Answer 42

Peyer patches are large collections of lymphoid nodules within the wall of the GI tract, particularly prominent in the ileum, and play a crucial role in immune defense.

Question 43

What might be a treatment option for chronic tonsillitis?

Answer 43

Chronic tonsillitis may require a tonsillectomy, which is the surgical removal of the tonsils.

Question 44

Explain the difference between diffuse lymphoid tissue and lymphoid nodules.

Answer 44

Diffuse lymphoid tissue consists of scattered lymphoid nodules that are not completely surrounded by a connective tissue capsule, while lymphoid nodules are more organized clusters of lymphoid cells.