Immune and Lymphatic System Vocabulary

Comprehensive vocabulary flashcards covering the anatomy, physiology, and pathology of the immune and lymphatic systems based on CCMA educational materials.

Lymphatic System

A structural system consisting of vessels, nodes, and organs that transport lymph, filter pathogens, and return interstitial fluid to the circulatory system.

Immune System

A functional system composed of specialized cells and chemical messengers that identify and inactivate pathogens to defend the body against disease.

Spleen

A lymphatic organ ($1 \times 3 \times 5$ inches) located in the upper left quadrant that filters old red blood cells, stores blood, and activates white blood cells during infection.

Thymus Gland

A lymphatic gland in the mediastinum that produces cells maturing into T cells; it is large in infants but shrinks and turns to fat in adults.

Tonsils

Pea-sized lymphatic tissues (lingual, palatine, and pharyngeal) that protect the entrance of the respiratory and digestive systems by filtering bacteria and viruses.

Peyer’s Patches

Bundles of lymph cells found in the wall of the ileum of the small intestine that contain B and T cells of the immune system.

Thoracic Duct

The drainage vessel for lymph from the majority of the body, which eventually empties into the left subclavian vein.

Leukocytes

White blood cells (WBCs) that protect the body against infection; they are classified into granulocytes and agranulocytes.

Cytokines

Chemical messengers secreted by white blood cells that direct the body’s immune response.

Granulocytes

A category of leukocytes characterized by heavily granulated cytoplasm and segmented nuclei, including neutrophils, eosinophils, and basophils.

Agranulocytes

A category of leukocytes with clear cytoplasm and a solid nucleus, including monocytes and lymphocytes.

Neutrophils (PMNs)

Granular leukocytes that perform phagocytosis by engulfing and destroying invading bacteria and viruses.

Phagocytosis

A cellular response meaning "cell eating" where immune cells like neutrophils or macrophages engulf and destroy pathogens.

Natural Killer (NK) Cells

Specialized lymphocytes that destroy host cells infected by viruses and cancer cells without previous sensitization.

Antigens

Nonself molecules or foreign pathogens that enter the body and stimulate an immune response.

Specific Immunity

A selective level of defense characterized by specificity and memory, building a targeted response to unique antigens over time.

Humoral Immunity

Also known as antibody-mediated immunity, this process involves B cells producing unique antibodies to bind with specific antigens.

Cell-Mediated Immunity

A type of specific immunity where T cells mount a direct attack against pathogens.

Helper T Cells

T cells that stimulate other T cell activity and assist B cells in producing antibodies.

IgG

The major antibody ($75\%$ to $85\%$ of total) in primary and secondary immune responses; it neutralizes toxins and crosses the placenta.

IgM

An antibody class ($5\%$ to $10\%$ of total) responsible for clumping antigens and for transfusion reactions in the ABO blood typing system.

Active Artificial Immunity

The type of long-term immunity obtained through deliberate action, such as receiving a vaccination.

Passive Natural Immunity

Short-term immunity developed when a body obtains antibodies from another person, such as a mother passing antibodies through breast milk.

Postexposure Prophylaxis (PEP)

A vaccination or immune treatment administered after an individual has potentially been exposed to a pathogen, such as hepatitis B.

Hemoglobin

A red pigment in erythrocytes composed of iron and protein that transports oxygen from the lungs to body cells.

Hematocrit

The measurement of the percentage of packed red blood cells in a volume of blood; its value is typically three times that of the hemoglobin value.

Thrombocytes

Also called platelets, these are the smallest formed elements of blood and are discoid fragments of megakaryocytes that initiate coagulation.

Pyrexia

The medical term for fever, a chemical response that stimulates the phagocytic process and inhibits pathogen activity.

Graves’ Disease

An autoimmune disorder where the immune system attacks the thyroid, causing hyperthyroidism (thyrotoxicosis).

Multiple Sclerosis (MS)

An autoimmune condition where the immune system attacks the protective myelin sheath of nerve fibers, causing inflammation and hardening into plaques.

Systemic Lupus Erythematosus (SLE)

A chronic inflammatory autoimmune disease characteristically associated with a "butterfly rash" on the face.

Myasthenia Gravis

An autoimmune disease where antibodies destroy acetylcholine (ACh) receptors, leading to muscle weakness and fatigue.

CD4+ Helper T cells

The specific immune cells targeted and destroyed by HIV, leading to severe immune deficiency.

Opportunistic Infections

Infections that occur more frequently or severely in individuals with damaged immune systems, such as PJP or Kaposi’s sarcoma.

Hodgkin’s Lymphoma

A cancer of the lymphatic system characterized by the presence of Reed-Sternberg cells circulating in the blood.

Multiple Myeloma

A cancer of the plasma cells where malignant cells produce M proteins instead of functional antibodies.