WK 1b Lymphoid organ and Immune system

What are the two primary lymphoid organs?

Bone marrow and thymus.

What is the site of adult hematopoiesis?

Bone marrow.

Where do T lymphocytes mature?

Thymus.

What is hematopoiesis?

The maturation of blood cells.

Where do most blood cell productions occur in adults?

In the pelvis.

What are the two types of bone marrow?

Red marrow and yellow marrow.

What part of the bone marrow is primarily responsible for blood cell production?

Red marrow.

What is the function of stromal cells in the bone marrow?

They provide the environment and secrete growth factors for immature blood cells.

What is the location of the thymus?

Behind the sternum in the mediastinum.

What are thymocytes?

Immature T cells that go to thymus for maturation.

What is the purpose of positive selection in the thymus?

To keep functional T cells.

What happens during negative selection in the thymus?

Destruction of T cells that recognize self-antigens.

What is autoimmune disease?

A condition where the immune system attacks its own tissues.

What is the clinical significance of thymic involution?

It contributes to a decline in immune response as we age.

What are secondary lymphoid organs?

Lymph nodes, spleen, tonsils, and Peyer's patches.

How does the lymphatic system function?

By returning excess interstitial fluid back to the bloodstream.

What is lymphadenopathy?

Enlarged lymph nodes due to infection or disease.

What are primary follicles in lymph nodes?

Groups of unactivated B cells.

What is the function of macrophages in lymph nodes?

To phagocytose pathogens and debris.

What is the purpose of MALT?

To support the immune system at mucosal surfaces.

What kind of antibodies do plasma cells produce in MALT?

IgA antibodies.

What are the three types of tonsils?

Palatine tonsils, adenoids, and lingual tonsils.

What happens when tonsils become inflamed?

Conditions like tonsillitis or pharyngitis occur.

Where are Peyer's patches primarily found?

In the small intestine.

What is the role of M cells in Peyer's patches?

To endocytose antigens and pathogens.

What is the spleen's main function related to blood?

Filtering old or damaged blood cells.

What is splenomegaly?

An enlarged spleen.

What are the two main components of splenic tissue?

Red pulp and white pulp.

What happens to red blood cells in the spleen?

They are filtered and old or damaged ones are phagocytosed.

What is extramedullary hematopoiesis?

Blood cell production outside the bone marrow, occurring in the spleen during fetal development or as a response to pathological states.

What is the hilum of the spleen?

The area where blood vessels enter and exit the spleen.

What is the periarteriolar lymphoid sheath?

A tissue in the spleen rich in T cells.

What is the primary role of T helper cells in a lymph node?

To help activate B cells.

What indicates that a lymph node is responding to an infection?

Lymphadenopathy, characterized by tender, swollen nodes.

What is the primary function of the thoracic duct?

To drain lymph from most of the body's lymphatic vessels into the left subclavian vein.

What is meant by antigen presenting cells?

Cells that capture and present antigens to T cells.

What is the main difference between lymph nodes and the spleen?

Lymph nodes filter lymph, whereas the spleen filters blood.

Why is the spleen important for the immune response?

It plays a crucial role in filtering pathogens and storing immune cells.

What happens to patients who have their spleen removed?

They are at increased risk for bacterial infections.

What kind of blood cells are primarily stored in the spleen?

Neutrophils and platelets.

What triggers the red blood cells to squeeze through the 3 micrometer holes in the spleen?

The filtration process to remove old cells.

What type of antibody is secreted by plasma cells in the gut associated lymphoid tissue?

IgA.

What happens to B cells when they are activated in the lymph nodes?

They mature into plasma cells that produce antibodies.

Which lymphatic organ contains the most antibody-producing plasma cells?

MALT.

What is a common sign of infection that affects lymph nodes?

Tenderness and swelling, indicating lymphadenopathy.

How can T and B cells encounter antigens?

Through the process that occurs in lymph nodes after antigen presentation.

How does the immune system protect mucosal surfaces?

Through MALT and the production of secretory antibodies.

What role do dendritic cells play in the immune response?

They present antigens to T cells and activate them.

What is the difference between systemic and localized lymphadenopathy?

Systemic involves multiple lymph nodes while localized affects lymph nodes near the site of infection.

What is the relationship between the spleen and extramedullary hematopoiesis in adults?

The spleen can reactivate blood cell production if the bone marrow is compromised.

What can cause the spleen to become enlarged?

Conditions like infections or blood disorders.

What is special about the lymphatic capillaries?

They have dead ends and start as cul-de-sac structures.

How do muscles aid the movement of lymph through lymphatic vessels?

Muscle contraction compresses lymphatic vessels to push lymph upward.

What classifies a lymph node's swelling as lymphadenopathy?

Swelling and inflammation due to response against pathogens.

What is the primary role of neutrophils in the spleen?

To respond to bacterial infections and provide innate immunity.

What are the two primary lymphoid organs?

Bone marrow and thymus.

What is the site of adult hematopoiesis?

Bone marrow.

Where do T lymphocytes mature?

Thymus.

What is hematopoiesis?

The maturation of blood cells.

Where do most blood cell productions occur in adults?

In the pelvis.

What are the two types of bone marrow?

Red marrow and yellow marrow.

What part of the bone marrow is primarily responsible for blood cell production?

Red marrow.

What is the function of stromal cells in the bone marrow?

They provide the environment and secrete growth factors for immature blood cells.

What is the location of the thymus?

Behind the sternum in the mediastinum.

What are thymocytes?

Immature T cells that go to thymus for maturation.

What is the purpose of positive selection in the thymus?

To keep functional T cells.

What happens during negative selection in the thymus?

Destruction of T cells that recognize self-antigens.

What is autoimmune disease?

A condition where the immune system attacks its own tissues.

What is the clinical significance of thymic involution?

It contributes to a decline in immune response as we age.

What are secondary lymphoid organs?

Lymph nodes, spleen, tonsils, and Peyer's patches.

How does the lymphatic system function?

By returning excess interstitial fluid back to the bloodstream.

What is lymphadenopathy?

Enlarged lymph nodes due to infection or disease.

What are primary follicles in lymph nodes?

Groups of unactivated B cells.

What is the function of macrophages in lymph nodes?

To phagocytose pathogens and debris.

What is the purpose of MALT?

To support the immune system at mucosal surfaces.

What kind of antibodies do plasma cells produce in MALT?

IgA antibodies.

What are the three types of tonsils?

Palatine tonsils, adenoids, and lingual tonsils.

What happens when tonsils become inflamed?

Conditions like tonsillitis or pharyngitis occur.

Where are Peyer's patches primarily found?

In the small intestine.

What is the role of M cells in Peyer's patches?

To endocytose antigens and pathogens.

What is the spleen's main function related to blood?

Filtering old or damaged blood cells.

What is splenomegaly?

An enlarged spleen.

What are the two main components of splenic tissue?

Red pulp and white pulp.

What happens to red blood cells in the spleen?

They are filtered and old or damaged ones are phagocytosed.

What is extramedullary hematopoiesis?

Blood cell production outside the bone marrow, occurring in the spleen during fetal development or as a response to pathological states.

What is the hilum of the spleen?

The area where blood vessels enter and exit the spleen.

What is the periarteriolar lymphoid sheath?

A tissue in the spleen rich in T cells.

What is the primary role of T helper cells in a lymph node?

To help activate B cells.

What indicates that a lymph node is responding to an infection?

Lymphadenopathy, characterized by tender, swollen nodes.

What is the primary function of the thoracic duct?

To drain lymph from most of the body's lymphatic vessels into the left subclavian vein.

What is meant by antigen presenting cells?

Cells that capture and present antigens to T cells.

What is the main difference between lymph nodes and the spleen?

Lymph nodes filter lymph, whereas the spleen filters blood.

Why is the spleen important for the immune response?

It plays a crucial role in filtering pathogens and storing immune cells.

What happens to patients who have their spleen removed?

They are at increased risk for bacterial infections.

What kind of blood cells are primarily stored in the spleen?

Neutrophils and platelets.

What triggers the red blood cells to squeeze through the 3 micrometer holes in the spleen?

The filtration process to remove old cells.

What type of antibody is secreted by plasma cells in the gut associated lymphoid tissue?

IgA.

What happens to B cells when they are activated in the lymph nodes?

They mature into plasma cells that produce antibodies.

Which lymphatic organ contains the most antibody-producing plasma cells?

MALT.

What is a common sign of infection that affects lymph nodes?

Tenderness and swelling, indicating lymphadenopathy.