Magnet Medical Science Unit 3B Test

What are the functions of the lymphatic system?

The lymphatic system functions to maintain fluid balance, filter pathogens, absorb fats, and facilitate immune responses.

What are the 4 major organs of the lymphatic system?

The four major organs are lymph nodes, spleen, thymus, and tonsils.

What is lymph?

Lymph is a clear fluid that circulates through the lymphatic system, containing immune cells and waste products.

What is interstitial fluid?

Interstitial fluid is the fluid that surrounds cells in tissues, providing nutrients and waste exchange.

What percentage of interstitial fluid diffuses into the capillaries and what percentage enters the lymphatic vessels?

About 85% of interstitial fluid diffuses into capillaries, while 15% enters lymphatic vessels.

What are lymph capillaries?

Lymph capillaries are small, thin-walled vessels that collect lymph from interstitial spaces.

What are lymph capillaries lined with?

Lymph capillaries are lined with endothelial cells that overlap to form one-way valves.

What are lymph vessels?

Lymph vessels are larger vessels that transport lymph from lymph capillaries to lymph nodes.

What are valves?

Valves are structures in lymph vessels that prevent the backflow of lymph.

How does a lymph pump work?

The lymph pump is facilitated by skeletal muscle contractions and movements of nearby organs.

What are capsules made of?

Capsules are made of connective tissue that surrounds lymph nodes and organs.

What is trabeculae?

Trabeculae are thin strands of connective tissue that divide the lymphatic organs into compartments.

What are germinal centers?

Germinal centers are areas in lymph nodes where B lymphocytes proliferate and mature.

What are efferent vessels and afferent vessels?

Afferent vessels carry lymph to the lymph nodes, while efferent vessels transport lymph away from the nodes.

What two ducts is the lymph eventually returned to?

The lymph is returned to the thoracic duct and the right lymphatic duct.

What are lymph nodes?

Lymph nodes are small, bean-shaped structures that filter lymph and house immune cells.

What are lymph nodules?

Lymph nodules are small, non-encapsulated clusters of lymphatic tissue found in mucosal areas; they differ from lymph nodes which are encapsulated.

What is white pulp?

White pulp is the part of the spleen that contains lymphocytes and is involved in immune responses.

What is red pulp?

Red pulp is the part of the spleen that filters blood and removes old red blood cells.

Where are T-lymphocytes formed and educated?

T-lymphocytes are formed in the bone marrow and educated in the thymus.

Where are lymph nodules found?

Lymph nodules are found in mucosal tissues throughout the body, including the gut and respiratory tract.

What does MALTS stand for?

MALTS stands for Mucosa-associated Lymphoid Tissue.

What can MALTS either be?

MALTS can either be organized (like lymphoid follicles) or diffuse lymphoid tissue.

What is mucous membrane?

Mucous membranes are moist layers of epithelium that line body cavities and secrete mucus.

What are tonsils?

Tonsils are lymphoid tissues located in the throat that help detect pathogens.

What are Peyer’s patches & appendix?

Peyer’s patches are clusters of lymphoid tissue in the intestines; the appendix is a pouch that contains lymphatic tissue.

What is the immune system?

The immune system is the body's defense mechanism against pathogens and diseases.

What are innate (non-specific) defenses?

Innate defenses are the body's first line of defense, involving barriers and immediate immune responses.

What are acquired (adaptive) defenses?

Acquired defenses are specific immune responses developed after exposure to pathogens.

What are external barriers?

External barriers include the skin and mucous membranes that prevent pathogen entry.

What are internal barriers?

Internal barriers include various immune cells and proteins that respond to infections.

What is skin?

The skin is the body's outer protective covering that acts as a barrier to pathogens.

What is a mucous membrane?

A mucous membrane is a protective layer lining body cavities that secretes mucus.

What are phagocytes?

Phagocytes are immune cells that engulf and digest pathogens and debris.

What are neutrophils?

Neutrophils are a type of white blood cell that responds quickly to infection.

What are macrophages?

Macrophages are large phagocytic cells that consume pathogens and help activate the immune response.

What are natural killer cells?

Natural killer cells are lymphocytes that attack infected or cancerous cells.

What is inflammation?

Inflammation is a localized immune response to injury or infection, characterized by redness, heat, swelling, and pain.

What are antimicrobial proteins?

Antimicrobial proteins are substances that inhibit microbial growth and infection.

What are complement proteins?

Complement proteins are enzymes that enhance the immune response by marking pathogens for destruction.

What are interferons?

Interferons are signaling proteins released by cells in response to viral infections.

What are cytokines?

Cytokines are signaling molecules that mediate and regulate immunity and inflammation.

What are the functions of acquired immunity?

The functions of acquired immunity include targeting specific pathogens, memory cell formation, and stronger responses upon re-exposure.

What is the humoral response?

The humoral response is the aspect of immunity that involves B cells and the production of antibodies against pathogens.

What is cell-mediated response?

Cell-mediated response involves T cells targeting and destroying infected cells.

What are B cells?

B cells are a type of lymphocyte responsible for producing antibodies.

What are T cells?

T cells are a type of lymphocyte that play a central role in cell-mediated immunity.

How is humoral immunity acquired?

Humoral immunity is acquired through exposure to pathogens or vaccination.

What is involved in cell-mediated response?

Cell-mediated response involves T cells recognizing and attacking infected cells.

What is secondary response?

Secondary response is the stronger and faster immune response that occurs upon re-exposure to a previously encountered pathogen.