Lymphatic and Immune System

Flashcards based on the Lymphatic and Immune System lecture notes for exam review.

Lymphatic system

Vessels, cells, and organs that carry excess fluids to the bloodstream.

Immune system

Collection of cells and organs that attack pathogens that would otherwise cause disease.

Lymph

Clear, colorless fluid located within lymphatic vessels.

Interstitial fluid

Straw-colored fluid located in spaces between cells.

Fluid Recovery

Transports excess interstitial fluid back to the bloodstream.

Lymphatic capillaries

Open-ended vessels that weave between tissue cells and blood capillaries.

Chyle

Fat in lymph.

Collecting vessels

Travel through many lymph nodes.

Lymphatic trunks

Drain major portions of the body.

Right lymphatic duct

Receives lymph from the right arm, right side of the head and thorax; empties into right subclavian vein.

Thoracic duct

Larger and longer duct that begins in the abdomen; receives lymph from below diaphragm, left arm, left side of head, neck, and thorax; empties into left subclavian vein.

Primary lymphoid organs

Organs where lymphocytes develop, including bone marrow and thymus.

T cells

Lymphocytes that travel to the thymus for maturation.

B cells

Lymphocytes that mature in bone marrow.

Lymph nodes

Bean-shaped nodes located along lymph vessels where lymphocytes encounter antigens.

Spleen

An organ involved in the immune response.

Mucosa-associated lymphoid tissue (MALT)

Tissues associated with mucous membranes, including Peyer’s patches, tonsils, and appendix.

Skin-associated lymphoid tissue (SALT)

Lymphoid tissue located in the skin.

Bronchus-associated lymphoid tissue (BALT)

Lymphoid tissue located in the bronchial region.

Gut-associated lymphoid tissue (GALT)

Lymphoid tissue located in the gut.

Innate immune response

Rapid but non-specific immune response to pathogens.

Adaptive immune response

Specific immune response that is powerful but slower.

B lymphocytes

Type of lymphocyte that produces antibodies.

T lymphocytes

Type of lymphocyte that uses other mechanisms to attack pathogens.

Plasma cells

Type of B cell that produces antibodies.

Natural Killer (NK) cells

Cells that are part of the innate immune response.

First Line of Defense

Barriers like skin and mucous membranes that prevent pathogen invasion.

Phagocytic cells

Cells that are part of the second line of defense, which include neutrophils and macrophages.

Cytokine

Signal molecule that allows cells to communicate.

Interferons

Proteins produced in response to viral infection that warn neighboring cells.

Complement system

Proteins that circulate in blood and provide a major mechanism for destroying foreign substances.

Membrane attack complex (MAC)

Complex that forms holes in the membranes of microbes, causing lysis.

Acute inflammation

A hallmark of the innate immune response characterized by redness, heat, swelling, and pain.

Mast cells

Cells that release vasodilatory chemicals during tissue injury.

Neutrophils

Most abundant white blood cells that respond first during inflammation.

Macrophages

Large white blood cells that follow neutrophils during inflammation.

Adaptive immunity

Specific defensive system that targets specific pathogens or abnormal cells.

Immunological memory

The ability of the immune system to respond more vigorously to pathogens it has encountered before.

Primary adaptive response

First exposure to a pathogen, often resulting in illness symptoms.

Secondary adaptive response

Stronger and faster response upon re-exposure to the same pathogen.

Humoral immunity

Branch of adaptive immunity involving B cells and antibody production.

Cell-mediated immunity

Branch of adaptive immunity involving T cells.

Thymus

Organ where T cells mature and are tested for self-tolerance.

MHC proteins

Major histocompatibility complex proteins that help T cells recognize antigens.

CD4 cells

Helper T cells that assist in coordinating the immune response.

CD8 cells

Cytotoxic T cells that directly attack infected or abnormal cells.

Antigen presenting cells (APCs)

Cells that engulf antigens, break them down, and present fragments to T cells.

Antibodies

Proteins secreted by plasma cells that identify and neutralize foreign objects.

Immunoglobulins (Igs)

Another term for antibodies.

IgM

First antibody produced during the primary immune response.

IgA

Antibody found in secretions like breast milk.

IgG

Antibody of secondary response that can cross the placenta.

IgE

Antibody associated with allergic reactions.

IgD

Antibody with largely unknown function, comprising less than 1% of antibodies.

Primary response

Initial immune response to a pathogen, often resulting in symptoms.

Secondary response

Re-exposure to the same pathogen yielding a quicker and stronger immune response.

Active immunity

Immunity gained through exposure to antigens and production of antibodies.

Passive immunity

Immunity gained through the introduction of ready-made antibodies.

Naturally Acquired Active Immunity

Immunity acquired through infection.

Naturally Acquired Passive Immunity

Immunity acquired through transfer of antibodies via placenta or breast milk.

Artificially Acquired Active Immunity

Immunity acquired through vaccination.

Artificially Acquired Passive Immunity

Immunity acquired through injection of antibodies.

Vasodilation

Widening of blood vessels during inflammation to increase blood flow.

Inflammatory response

The body's response to injury that involves redness, heat, swelling, and pain.

Interferons

Proteins that help cells resist viral infections and alert neighboring cells.

Memory T cells

Long-lived T cells that are reactivated upon encountering a previously known antigen.

Plasma cells

B cells that produce antibodies in response to antigens.

Antigen-antibody complex

Complex formed when antibodies bind to their specific antigens.

Phagocytosis

Process by which phagocytes engulf and destroy pathogens.

Vasodilatory chemicals

Chemicals released by mast cells that promote vasodilation.

Cellular Immunity

Immune response that involves the direct action of T cells against infected or abnormal cells.

B cell differentiation

Process by which B cells mature and become plasma cells or memory cells.

Pattern recognition receptors

Molecules that allow the immune system to recognize common patterns in pathogens.