Lymphatic System & Immunity

Vocabulary practice flashcards covering the anatomy, pathways, histology, cellular components, antibodies, and mechanisms of the lymphatic system and immunity.

Lymph

A clear fluid that carries immune cells throughout the lymphatic network.

SUPERFICIAL LYMPH NODES

Located in the subcutaneous tissue directly beneath the skin

(e.g., Axillary nodes).

DEEP LYMPH NODES

Located deeply within body cavities (e.g., deep thoracic nodes near the Thymus).

Lacteal

Specialized lymphatic capillaries found in the lining of the digestive tract.

Chyle

Milky white fluid formed in the small intestine during the digestion of fatty acids.

IgG

The most abundant type of antibody in the body.

IgA

An antibody found in breast milk, saliva, and mucus.

IgM

The first type of antibody to respond during an immune response.

IgE

An antibody associated with allergic reactions or pancreatic infection.

IgD

An antibody that helps B cell functions.

B Cells

Immune cells that originate and mature in the red bone marrow to create and produce antibodies.

T Cells

Immune cells that originate in the red bone marrow and mature in the thymus to destroy and kill cancerous or infected cells.

Jugular Trunk

A lymphatic trunk that drains lymph from the head and neck.

Subclavian Trunk

A lymphatic trunk that drains lymph from the upper limbs, superficial thoracic wall, and mammary glands.

Bronchomediastinal Trunk

A lymphatic trunk that drains lymph from the thoracic organs and the deep thoracic wall.

Intestinal Trunk

A lymphatic trunk that drains lymph from the abdominal organs.

Lumbar Trunk

A lymphatic trunk that drains lymph from the lower limbs.

Right Lymphatic Duct

A major lymphatic duct that collects and drains lymph exclusively from the right upper quadrant (right side of head, neck, thorax, and right arm).

Thoracic Duct

A major lymphatic duct that drains lymph from the entire rest of the body except the right upper quadrant.

Afferent Lymphatic Vessels

Vessels that bring unfiltered lymph into a lymph node.

Efferent Lymphatic Vessels

Vessels that carry filtered lymph away or out of a lymph node.

Lymph Node

Round, oval, or bean-shaped bodies distributed along the lymphatic system that filter fluid.

Capsule (Lymph Node)

A dense connective tissue outer covering that surrounds each lymph node.

Trabeculae

Internal extensions of the lymph node capsule that form a delicate internal structural skeleton.

MALT (Mucosa-Associated Lymphoid Tissue)

Aggregates of non-encapsulated lymphatic tissue found in and beneath mucous membranes (such as the digestive, respiratory, urinary, and reproductive tracts) to protect vulnerable entry areas.

Tonsils

Large groups of lymphatic nodules and diffuse lymphatic tissue located deep to the mucous membranes within the pharynx.

Pharyngeal Tonsil

A tonsil located at the top of the pharynx (nasopharynx).

Palatine Tonsils

Tonsils located at the back of the throat that are highly prone to infection.

Lingual Tonsils

Tonsils located at the base of the tongue.

Tonsillitis

Inflammation of the tonsils.

Tonsillectomy

Surgical removal of the tonsils.

White Pulp

Lymphatic tissue surrounding the central arteries within the spleen that handles immune surveillance.

Red Pulp

Vascular tissue associated with veins in the spleen that stores blood and filters damaged red blood cells.

Hilum (Spleen)

The entrance or indentation where the splenic artery, splenorenal branches, veins, and nerves enter and exit the spleen.

PALS (Periarterial Lymphatic Sheath)

Diffuse lymphatic tissue surrounding arteries and arterioles in the spleen that extends to lymphatic nodules.

Splenic Cord

Structures in the spleen that form a reticular cell network producing reticular fibers.

Venous Sinuses (Spleen)

Enlarged capillaries located between splenic cords that connect to trabecular veins, eventually merging to form the splenic vein.

Thymus

A bilobed gland in the superior mediastinum of the thoracic cavity that secretes thymosin hormone and serves as the maturation site for T-cells.

Regulatory T-Cells

Cells that suppress the body's immune response to protect against autoimmune diseases.

Innate Immunity

The body's natural, non-specific first line of defense that acts fast, provides general protection, and has no memory.

Adaptive Immunity

A specialized, acquired immune defense that is specific, slow to develop, and retains memory of previous encounters.

Chemotactic Factors

Chemical signals that attract white blood cells toward specific areas.

Chemotaxis

The ability of white blood cells (WBCs) to move toward an infected organ.

Neutrophil

Small phagocytic granulocyte white blood cells produced in large numbers in the red bone marrow that engulf bacteria and fungi via oxidative burst.

Pus

An accumulation of dead neutrophils.

Monocyte / Macrophage

Mononuclear white blood cells that engulf bacteria, fungi, and cellular debris, produce cytokines, and carry out antigen processing.

Eosinophil

A granulocyte white blood cell associated with allergic responses and parasitic infections.

Basophil

A granulocyte white blood cell associated with hypersensitivity that releases histamine.

Mast Cell

A bone marrow-derived cell containing granules with vasoactive amines like histamine, and proteases that kill bacteria.

Natural Killer (NK) Cell

A lymphocyte white blood cell that recognizes stressed or infected cells and destroys them by secreting the macrophage-activating cytokine IFN-γ.

Dendritic Cell

A bone marrow-derived cell responsible for phagocytosis, antigen processing and presentation (APC), and initiating T-cell responses.

Antibody-Mediated Immunity

Adaptive humoral immunity mediated by antibodies circulating in extracellular fluids such as plasma, interstitial fluid, and lymph.

Cell-Mediated Immunity

Adaptive immunity mediated by the direct action of specialized T lymphocytes, such as cytotoxic T cells.

Foreign Antigens

Molecules not produced by the body that are introduced from the outside environment to stimulate an immune response.

Self Antigen

Molecules produced or processed within the body that stimulate an adaptive immune system response.

Antiserum

A general term for an injection containing antibodies responsible for providing passive artificial immunity (e.g., antirabies).

Naturally-Acquired Active Immunity

Adaptive immunity in which immune products are acquired following natural exposure to an antigen (such as contracting the flu).

Naturally-Acquired Passive Immunity

Adaptive immunity resulting from the non-medical transfer of antibodies, such as IgG transferred through the placenta or IgA through breast milk.

Artificially-Acquired Active Immunity

Adaptive immunity in which immune products are developed following vaccination with antigens that are immunogenic but not pathogenic.

Artificially-Acquired Passive Immunity

Adaptive immunity acquired through a prepared injection of antibodies (e.g., antirabies).