Chapter 22 Lecture Notes Flashcards

Vocabulary flashcards based on the provided lecture notes on the lymphatic and immune systems.

Resistance

The ability to ward off pathogens that produce disease.

Susceptibility

Lack of resistance to disease.

Innate Immunity (Nonspecific Resistance)

Present at birth; defense mechanisms provide general protection against a wide range of pathogens.

Immunity

Activation of specific lymphocytes that combat a particular pathogen or other foreign substance.

Lymphatic System

The body system that carries out immune responses.

Lymph

Fluid flowing within lymphatic vessels.

Lymphatic Tissue

Specialized reticular tissue containing large numbers of lymphocytes.

Lymphatic Vessels

Vessels that convey lymph into and out of lymph nodes.

Lymph Nodes

Structures along lymphatic vessels containing lymphatic tissue (T cells, macrophages, follicular dendritic cells, and B cells).

Lymph Capillaries

Blind-ended vessels in tissue spaces between cells where interstitial fluid drains to form lymph.

Lacteal

Lymphatic capillary in the villus of the small intestine for transporting digested fats.

Lymph Trunks

Principal vessels formed from exiting vessels of lymph nodes (lumbar, intestinal, bronchomediastinal, subclavian, and jugular trunks).

Thoracic Duct

Main collecting duct of the lymphatic system, receiving lymph from the left side of the head, neck, and chest, the left upper extremity, and the entire body below the ribs.

Cisterna Chyli

Dilation at the beginning of the thoracic duct.

Right Lymphatic Duct

Drains lymph from the upper right side of the body.

Primary Lymphatic Organs

Organs where cells become immunocompetent; red bone marrow (B cells) and thymus gland (T cells).

Secondary Lymphatic Organs

Lymph nodes and spleen, where most immune responses occur.

Lymphatic Nodules

Secondary lymphatic tissues.

Thymus Gland

Site of T cell maturation, located between the sternum and the heart.

Spleen

Largest mass of lymphatic tissue in the body, filters blood, stores platelets, and removes worn-out blood cells.

White Pulp

Lymphatic tissue in the spleen where T lymphocytes directly attack and destroy antigens in blood.

Red Pulp

Venous sinuses filled with blood and splenic cords in the spleen, involved in removing worn-out blood cells and storing platelets.

MALT (Mucosa-Associated Lymphatic Tissue)

Lymphatic nodules scattered throughout the lamina propria of mucous membranes lining the GI tract, respiratory airways, urinary tract, and reproductive tract.

Peyer’s Patches

Lymphatic nodules in the ileum of the small intestine.

Tonsils

Multiple aggregations of large lymphatic nodules embedded in a mucous membrane at the junction of the oral cavity and the pharynx.

Innate Immunity

Wide variety of body responses against a wide range of pathogens and their toxins; present at birth.

Lysozyme

Enzyme component of sweat that has antimicrobial properties.

Interferons (IFNs)

Proteins produced by lymphocyte and macrophage cells infected with viruses that induce uninfected cells to synthesize antiviral proteins.

Complement System

Group of about 20 proteins in blood plasma and on cell membranes that enhance certain immune, allergic, and inflammatory reactions.

Natural Killer (NK) Cells

Lymphocytes that lack membrane molecules that identify T and B cells and have the ability to kill a wide variety of infectious microbes.

Phagocytes

Cells specialized to perform phagocytosis, including neutrophils and macrophages.

Chemotaxis

First phase of phagocytosis; chemical attraction of phagocytes to a site of infection.

Phagolysosome

Structure formed during phagocytosis when a phagosome fuses with a lysosome.

Inflammation

Body response to cell damage characterized by redness, pain, heat, and swelling.

Histamines

Substances that contribute to inflammation.

Pus

Pocket of dead phagocytes, damaged tissue, and fluid formed after phagocytes engulf damaged tissue and microbes.

Fever

Abnormally high body temperature, often caused by infection.

Antigens

Substances recognized as foreign by the immune responses.

Specificity

Distinguishing property of immunity; ability to recognize specific antigens.

Memory

Distinguishing property of immunity; ability to 'remember' prior encounter with an antigen.

Cell-Mediated Immunity

Destruction of antigens by T cells; effective against intracellular pathogens, some cancer cells, and foreign tissue transplants.

Antibody-Mediated (Humoral) Immunity

Destruction of antigens by antibodies; works against antigens dissolved in body fluids and extracellular pathogens.

Clonal Selection

Process by which an immune cell proliferates and differentiates in response to a specific antigen.

Effector Cells

Cells that actively work to destroy an antigen, including cytotoxic T cells, helper T cells, and plasma cells.

Memory Cells

Long-lived cells that provide a faster second invasion response by proliferating and differentiating into effector cells.

Antigenic Determinants (Epitopes)

Specific portions of antigen molecules that trigger immune responses.

MHC (Major Histocompatibility Complex) Antigens

Unique self-antigens on body cells that aid in the detection of foreign invaders.

Antigen-Presenting Cells (APCs)

Cells (e.g., macrophages, B cells, dendritic cells) that process exogenous antigens and present them together with MHC class II molecules to T cells.

Cytokines

Small protein hormones needed for many normal cell functions, including immune responses.

Helper T (TH) Cells

T cells that display CD4 protein, recognize antigen fragments associated with MHC-II molecules, and secrete cytokines.

Cytotoxic T (TC) Cells

T cells that display CD8 protein and recognize antigen fragments associated with MHC-I molecules.

Immunological Surveillance

Process carried out by cytotoxic T cells to recognize and destroy tumor cells.

Antibody

Protein that can combine specifically with the antigenic determinant on the antigen that triggered its production.

Hybridoma

A cell created by fusing a B cell with a tumor cell that is capable of proliferating endlessly, it produces monoclonal antibodies.

Monoclonal Antibodies

Pure antibodies produced by a hybridoma. Important in measuring levels of a drug in a patient’s blood and in the diagnosis of pregnancy, allergies, and diseases.

Immunological Memory

Due to the presence of long-lived antibodies and very long-lived lymphocytes that arise during proliferation and differentiation of antigen-stimulated B and T cells.

Self-Recognition

The ability of T cells to recognize self-MHC antigens.

Self-Tolerance

The mechanism that ensures that T cells do not react to other self-proteins.

Psychoneuroimmunology (PNI)

The field that deals with common pathways that link the nervous, endocrine, and immune systems.

AIDS (Acquired Immunodeficiency Syndrome)

Condition in which a person experiences infections as a result of the progressive destruction of immune cells by HIV.

HIV (Human Immunodeficiency Virus)

Retrovirus that causes AIDS by infecting and destroying T cells.

Opportunistic Infections

Invasion of normally harmless microorganisms that now proliferate wildly because of the defective immune system in AIDS patients.

Hypersensitivity (Allergy)

Overly reactive response to a substance that is tolerated by most others; causes tissue injury.

Allergens

Antigens that induce an allergic reaction.

Anaphylaxis

Type I hypersensitivity reaction that occurs within minutes after reexposure to an allergen; can lead to anaphylactic shock.

Autoimmune Disease

Condition in which the immune system fails to display self-tolerance and attacks the person’s own tissue.

Lymphomas

Cancers of the lymphatic organs, especially the lymph nodes.