Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
135 Cards in this Set
- Front
- Back
Ability to ward off pathogens that produce disease.
|
Immunity/resistance
|
|
Lack of resistance.
|
Susceptibility
|
|
Type of immunity that protects against wide range of pathogens.
|
Innate (nonspecific) immunity
|
|
Type of immunity that involves specific lymphocytes that combat a particular pathogen/foreign substance.
|
Adaptive (specific) immunity
|
|
What is the major difference b/w interstitial fluid & lymph?
|
Interstitial fluid is found b/w cells. Lymph is found within lymphatic vessels/tissue.
|
|
What are 4 functions of the lymphatic system?
|
1. Drain excess interstitial fluid & return to blood
2. Return leaked plasma proteins to blood 3. Transport lipids & lipid-soluble vitamins from GIT to blood 4. Carries out immune response (specific, nonspecific). |
|
What tissues lack lymphatic capillaries?
|
Avascular (cartilage, skin, cornea of eye), CNS, parts of spleen, red bone marrow.
|
|
Interstitial fluid drains into ___ which merge to form larger ___ & these convey lymph in/out ___.
|
Lymph capillaries. Lymph vessels. Lymph nodes.
|
|
How do lymph vessels compare to vein structure?
|
Lymph vessels have thinner walls & more valves.
|
|
How are valves structured in lymph capillaries?
|
Overlapping endothelial cells work as 1-way valves. Open like swinging door when IF pressure is greater than lymph.
|
|
Anchoring filaments
|
Elastic fibers that extend out to attach lymph vessel to surrounding tissues. Help open endothelial spaces in vessels when there is excess fluid.
|
|
___ formed in the small intestine during digestion of fatty foods, and taken up by lymph vessels specifically known as ___ (lymphatic capillary that absorbs dietary fats in the villi of the small intestine)
|
Chyle / Lacteals
|
|
What are the 5 principle lymph trunks?
|
Lumbar, intestinal, bronchomediastinal, subclavian, jugular trunks.
|
|
Lymph trunk that drains lower limbs, wall/viscera of pelvis, kidneys, adrenal glands, abdominal wall.
|
Lumbar trunk
|
|
Lymph trunk that drains stomach, intestines, pancreas, spleen, part of liver.
|
Intestinal trunk
|
|
Lymph trunk that drains thoracic wall, lungs, heart.
|
Bronchomediastinal trunk
|
|
Lymph trunk that drains upper limbs.
|
Subclavian trunk
|
|
Lymph trunk that drains head, neck.
|
Jugular trunk
|
|
Main collecting duct of lymphatic system which begins as dilation called ___. Collects from L side of head, neck, chest, L upper limb, entire body below ribs.
|
Thoracic duct. Chyle cistern.
|
|
Main duct that collects from upper R side of body.
|
Right lymphatic duct
|
|
Where do the 2 main lymph ducts drain into?
|
Junction of subclavian vein & internal jugular vein. (L - thoracic duct, R - right lymphatic duct)
|
|
Which lymphatic vessels empty into cisterna chyli, & which duct receives lymph from cisterna chyli?
|
L/R lumbar trunks & intestinal trunk empty into cisterna chyli, which drain into thoracic duct.
|
|
What are the 2 pumps that result in milking of lymph?
|
Skeletal mm, respiratory.
|
|
Primary lymphatic organs are areas where stem cells divide to become immunocompetent. List 2.
|
Red bone marrow, thymus.
|
|
Secondary lymphatic organs/tissue are sites where most immune responses occur. List 3.
|
Lymph nodes, spleen, lymph nodules (tissue)
|
|
The thymus gland lies b/w what 2 structures? What is its function?
|
Heart & sternum. Function - site of T-cell maturation.
|
|
Thymus has 2 ___ separated by capsule w/ extensions called ___ that divide lobe into lobules.
|
Lobes. Trabeculae.
|
|
The outer cortex of thymus lobules contain what structures? What is its function?
|
T cells, dendritic cells, epithelial cells, macrophages. Site of T-cell maturation (help from dendritic cells).
|
|
What does the medulla of thymus lobules contain that the cortex doesn't?
|
Thymic (Hassal's) corpuscles - possibly site of T-cell death.
|
|
When is the thymus gland the largest in life? What is it replaced by & when?
|
Largest in infants. After puberty it is replaced by adipose, areolar CT.
|
|
Where are large groups of lymph nodes found?
|
Near mammary glands, axillae, groin.
|
|
Encapsulated oval structures located along lymphatic vessels. Approx 600 in body. Contain T-cells, macrophages, follicular dendritic cells, B cells.
|
Lymph nodes
|
|
Capsule surrounding lymph nodes extend projections called ___ into node to divide it into compartments.
|
Trabeculae
|
|
Capsule, trabeculae, reticular fibers, fibroblasts constitute ___ of lymph node.
|
Stroma (supporting CT)
|
|
Functioning part of lymph node.
|
Parenchyma
|
|
Area of lymph node that has lymphatic follicles (nodules) which are aggregates of B cells & have germinal centers.
|
Outer cortex
|
|
Area of lymph node that has T cells, dendritic cells which present antigen & cause T cells to proliferate & migrate to infection area.
|
Inner cortex
|
|
Area of lymph node that has B cells, macrophages, antibody producing plasma cells.
|
Medulla
|
|
Depression in lymph node where efferent lymphatic vessels emerge & where BV enter/leave node.
|
Hilum
|
|
What cells destroy foreign substances by phagocytosis? What cells destroy by immune responses?
|
Macrophages. Lymphocytes.
|
|
What is the route of the lymph through lymph node (5 steps)?
|
Afferent vessels, subcapsular sinus, trabecular sinus, medullary sinus, efferent vessels.
|
|
Foreign substances filtered by lymph nodes are trapped by ___.
|
Nodal reticular fibers
|
|
Lymph nodes are site of proliferation for what 2 cell types?
|
Plasma cells, T-cells.
|
|
Largest single mass of lymphatic tissue in the body.
|
Spleen
|
|
What region is the spleen found in the body?
|
Left hypochondriac region (b/w stomach & diaphragm).
|
|
What travels through the spleen's hilum?
|
Splenic artery, vein, efferent lymph vessels.
|
|
Spleen's white pulp is formed by ___ arranged around central arteries.
|
Lymphatic tissue
|
|
What are the 2 types of lymphocytes in the spleen's white pulp & their functions?
|
T-lymphocytes attack/destroy antigens in blood. B-lymphocytes become antibody producing plasma cells (antibodies inactivate antigens in blood).
|
|
What is the role of macrophages in the white pulp vs. red pulp of the spleen?
|
White pulp - destroy antigens in blood via phagocytosis. Red pulp - remove worn-out/defective RBCs, WBCs, platelets.
|
|
Spleen's red pulp consists of ___ filled w/ blood & splenic cords consisting of what 5 cell types?
|
Venous sinuses. RBCs, macrophages, lymphocytes, plasma cells, granulocytes.
|
|
Which part of spleen produces blood cells in fetus during 2nd trimester pregnancy?
|
Red pulp
|
|
Oval shaped concentrations of lymphatic tissue not surrounded by a capsule.
|
Lymphatic nodules
|
|
Lymphatic nodules scattered through ___ of mucus membranes lining what areas? Named mucosa-associated lymphatic tissue (MALT).
|
Lamina propria. GI tract, respiratory airways, urinary & reproductive tracts.
|
|
Lymphatic nodules in ileum of small intestine.
|
Peyer's patches
|
|
Groups of large lymphatic nodules embedded in mucous membrane at junction of oral cavity & pharynx.
|
Tonsils
|
|
What are the 3 tonsils & which is commonly removed?
|
Pharyngeal (adenoid), palatine (removed often), lingual.
|
|
List body structures/substances that aid as first line of defense.
|
Skin, mucous membranes, cilia in respiratory tract, gastric juice, lysozome in tears/perspiration, saliva, urine, defecation, vomiting, vaginal secretions.
|
|
What are 5 types of 2nd line of defense?
|
Internal antimicrobial substances, phagocytes, NK cells, inflammation, fever.
|
|
What are the 4 types of antimicrobial substances?
|
Interferons, complement, iron-binding proteins, antimicrobial proteins.
|
|
Type of antimicrobial substance produced by lymphocytes, macrophages, fibroblasts infected w/ viruses. Bind to surrounding uninfected cells which induces antiviral protein synthesis & interferes w/ viral replication.
|
Interferons (IFNs)
|
|
Group of 30 proteins in blood plasma & cell membranes that when activated, enhance certain immune, allergic, inflammatory reactions.
|
Complement system
|
|
Type of antimicrobial substance that inhibits growth of bacteria by reducing amount of iron available.
|
Iron-binding proteins
|
|
Type of antimicrobial substance that have broad spectrum of antimicrobial activity (eg. Dermicidin, defensins, cathelicidins, thrombocidin).
|
Antimicrobial proteins
|
|
Lymphocytes that lack membrane molecules that identify T & B cells. Attack cells that display abnormal plasma membrane proteins.
|
Natural killer cells
|
|
What 2 types of toxic substances are found in granules released by NK cells?
|
Perforins (punch holes in target cell, causing it to burst), granzymes (force cell to undergo apoptosis).
|
|
What are 2 types of phagocytes?
|
Neutrophils, macrophages.
|
|
What are 2 classes of macrophages?
|
Wandering, fixed.
|
|
What are the 5 phases of phagocytosis?
|
Chemotaxis, adherence, ingestion, digestion, killing.
|
|
Anything that can't be digested in phagocyte remains in ___.
|
Residual bodies
|
|
What are reasons why a microbe can evade phagocytosis?
|
Capsule formation, toxin production, interference w/ lysozyme secretion, ability to counter oxidants produced by phagocytes.
|
|
What factors may stimulate chemotaxis?
|
Microbes, WBCs, damaged tissue, activated complement system
|
|
Nonspecific, defensive response occuring due to pathogens, abrasions, chemical irritations, distortions, extreme temps, disturbances of cells.
|
Inflammation
|
|
What are 5 symptoms of inflammation?
|
Swelling, heat, a loss of function, redness, pain (SHARP)
|
|
What are 3 basic stages of inflammation?
|
Vasodilation & increased permeability of blood vessels, phagocyte migration, tissue repair.
|
|
Substance released from mast cells causing vasodilation, increased permeability of vessels. Contributes to inflammation.
|
Histamines
|
|
Polypeptide that induces vasodilation, increases permeability, acts as chemotaxic agents (bradykinin). Contributes to inflammation.
|
Kinins
|
|
Lipid released by damaged cells that intensify effects of histamine & kinins. Stimulate emigration of phagocytes through capillary walls. Contributes to inflammation.
|
Prostaglandins
|
|
Substance produced by basophils, mast cells and cause increased permeability, act as chemotaxic agents, help w/ adherence of phagocytes to pathogens. Contributes to inflammation.
|
Leukotrienes
|
|
Substance that stimulates histamine release, attract neutrophils, promote phagocytosis, destroy bacteria.
|
Complement
|
|
What are 5 substances that contribute to inflammation?
|
Histamines, kinins, prostaglandins, leukotrienes, complement.
|
|
How long does it take for phagocytes to arrive to area of inflammation?
|
Within hour
|
|
What cell is the first responder to a site of inflammation? What cell comes next & cleans up the dead cells above?
|
Neutrophils. Monocytes become wandering macrophages.
|
|
Increase in WBCs in blood.
|
Leukocytosis
|
|
Pocket of dead phagocytes, damaged tissue & fluid that occurs in most inflammatory responses.
|
Pus
|
|
Excessive accumulation of pus in a confined space.
|
Abscess
|
|
What usually causes fever? How does a fever affect body processes?
|
Caused when thermostat of hypothalamus is reset due to bacterial toxins, viruses. Intensifies effect of interferons, stops growth of microbes, speeds repair reactions.
|
|
What 2 properties distinguish adaptive immunity vs. innate?
|
Specificity, memory.
|
|
T-cells & B-cells derive from stem cells located in ___.
|
Bone marrow
|
|
What is the difference in which T-cells & B-cells mature?
|
B cells mature in bone marrow (continues thru life). T cells develop from pre-T cells that migrate to thymus (most arise before puberty but continues thru life).
|
|
Ability to carry out adaptive immune responses.
|
Immunocompetence
|
|
Molecules capable of recognizing specific antigens.
|
Antigen receptors
|
|
T-cells exit thymus as what 2 types of cells?
|
Helper (CD4) T cell , Cytotoxic (CD8) T cell
|
|
What are 2 types of adaptive immunity?
|
Cell-mediated immunity, antibody-mediated immunity.
|
|
Type of adaptive immunity where cytotoxic T-cells attack other cells (antigens). Ex, INTRAcellular pathogens - fungi, parasites, viruses, some cancer cells, foreign tissue transplants.
|
Cell-mediated immunity
|
|
Type of adaptive immunity - B cells transform into plasma cells & secrete antibodies/immunoglobins that attach to antigens. Helper T-cells aid in both cell/antibody-mediated responses. Effective against antigens dissolved in fluid & EXTRAcellular pathogens - bacteria.
|
Antibody-mediated immunity
|
|
Process by which a lymphocyte proliferate & differentiate in response to a specific antigen.
|
Clonal selection
|
|
Population of identical cells that can recognize the same specific antigen as original lymphocyte.
|
Clone
|
|
Where does clonal selection of lymphocytes occur?
|
Secondary lymphatic organs/tissues.
|
|
A lymphocyte that undergoes clonal selection gives rise to what 2 major cell types?
|
Effector & memory cells
|
|
What are 3 types of effector cells vs. memory cells? What is the difference in their life spans?
|
EFFECTOR - Active helper T-cell, active cytotoxic T-cell, plasma cell - die after immune response. MEMORY - memory helper T-cell, memory cytotoxic T-cell, memory B cells - long life span.
|
|
Chemical substances (usually protein) recognized as foreign by antigen receptors. Immunogenic & reactive.
|
Antigens
|
|
Antigen's ability to provoke immune response by stimulating production of specific antibodies/T cells.
|
Immunogenic
|
|
Ability of antigen to react w/ specific antibodies/cells it provoked.
|
Reactive
|
|
Which parts of bacterial structures are antigenic?
|
Flagella, capsules, cell walls, bacterial toxins.
|
|
Specific portions of antigen molecules that trigger immune responses.
|
Epitopes (antigenic determinants)
|
|
What are 3 routes that antigens use to get to lymphatic tissue?
|
Enter bloodstream & get trapped in spleen, penetrate skin & enter lymphatic vessels & lodge in lymph nodes, get trapped in mucosa-associated lymphatic tissue.
|
|
Small substance w/ no immunogenicity but can stimulate immune response (reactivity) if attached to larger carrier molecule.
|
Haptens
|
|
Process where gene segments are put together in different combos as lymphocytes are developing in red bone marrow & thymus.
|
Genetic recombination
|
|
Transmembrane glycoproteins that are self-antigens unique to each person's cells. MHC class 1 found in all cells except RBCs. Aid in detection of foreign invaders.
|
Major histocompatibility complex (MHC)
|
|
What is the difference in which T-cells & B-cells recognize foreign antigens?
|
B cells recognize & bind to antigens in ECF (blood plasma, lymph). T cells only recognize fragments of antigenic proteins that have been processed/presented in association w/ MHC (self-antigen).
|
|
Antigen-presenting cells (APCs) process (exogenous/endogenous) antigens & present them w/ MHC (class 1/2) molecules to T cells. After presenting antigen, APCs migrate to lymph nodes.
|
Exogenous. MHC class 2.
|
|
What are 3 types of antigen-presenting cells? Where are they located in the body?
|
Macrophages, B cells, dendritic cells. Skin, mucus membranes of respiratory tract, GIT, urinary, reproductive, lymph nodes.
|
|
What are the 7 steps of processing/presenting an exogenous antigen?
|
Ingestion of antigen. Digestion of antigen into peptide fragments. Synthesis of MHC-2 molecules. Packaging of MHC-2 molecules. Fusion of vesicles. Binding of peptide fragments to MHC-2 molecules. Insertion of antigen-MHC-2 complexes into plasma membrane.
|
|
(Exogenous/endogenous) antigens are synthesized within body & include viral proteins or proteins produced by cancer cells.
|
Endogenous
|
|
What are the 5 steps of processing/presenting an endogenous antigen?
|
Digestion of antigen into peptide fragments, synthesis of MHC-1 molecules, binding of peptide fragments to MHC-1 molecules, packaging of antigen-MHC-1 molecules into vesicle, insertion of antigen-MHC-1 complexes into plasma membrane.
|
|
Small protein hormones needed for many normal cell functions such as cell growth, differentiation. Secreted by various types of cells, including lymphocytes & APCs.
|
Cytokines
|
|
What 2 signals activate a T-cell to undergo clonal selection?
|
1) Antigen recognition by T-cell receptor w/ CD4 or CD8 protein. 2) Costimulation by cytokines or pair of plasma membrane molecules (one on T-cell, one on antigen-presenting cell).
|
|
Recognition & binding of T-cell receptor/antigen without costimulation leads to prolonged state of inactivity called ___ in T & B cells.
|
Anergy
|
|
In clonal selection of helper T-cells, what is the effector & memory cell?
|
Active helper T-cell (secretes interleukin-2 & other cytokines), memory helper T-cell.
|
|
In clonal selection of cytotoxic T-cells, what is the effector & memory cell?
|
Active cytotoxic T-cell (attack infected body cells), memory cytotoxic T-cell.
|
|
What are 4 ways cytotoxic T-cells can kill cells displaying microbial antigen?
|
Granzymes (apoptosis - phagocytes eat released microbes), perforin (cytolysis) & granulysin (destroys microbe), lymphotoxin (target cell DNA fragmentation).
|
|
Success of proposed organ/tissue transplant depends on ___.
|
Histocompatibility
|
|
Process where cytotoxic T-cells, macrophages, NK cells recognize tumor antigens on cancerous cells & destroy tumor cell.
|
Immunological surveillance
|
|
In clonal selection of B-cells, what is the effector & memory cell?
|
Plasma cells, memory B cells
|
|
Of T-cells & B-cells, which one leaves tissue & which stays put?
|
T cells leave tissue, B cells stay put.
|
|
Protein that can combine specifically w/ epitope that triggered its production.
|
Antibody
|
|
Which part of the antibody is the antigen binding site?
|
Tip of heavy/light chains have variable region.
|
|
Which part of the antibody gives us the 5 classes of immunoglobulins?
|
Constant region
|
|
What are 6 functions of antibodies?
|
Neutralize antigen, immobilize bacteria (cilia/flagella), agglutination & precipitation (clumping of antigens), complement activation, enhances phagocytosis (stem waves like flag).
|
|
What are the 3 pathways that activate the complement system?
|
Classical (Ab bind to antigens), alternative (microbe lipid-carb complex binds to complement factors B,D,F), lectin (macrophages causes liver to produce lectins that bind to microbes).
|
|
What 4 results occur because of complement system?
|
Phagocytosis, cytolysis, inflammation, chemotaxis
|
|
Immunological memory is due to presence of long-lived ___ & ___.
|
Antibodies, lymphocytes.
|
|
Is self-recognition of T-cells (positive/negative) selection? Where does it occur? What happens?
|
Positive selection. Thymic cortex - pre-T cells that recognize MHC on epithelial cells survive.
|
|
Is self-tolerance of T-cells (positive/negative) selection? Where does it occur? What happens?
|
Negative selection. Junction cortex & medulla of thymus. T-cells that recognize self-peptide/self-antigen are deleted (apoptosis) or stay in anergy (alive, unresponsive). Those that don't respond survive.
|
|
What occurs w/ aging of immune system?
|
More susceptible to infections/malignancies, response to vaccines decrease, more autoantibodies produced. Cellular/humoral responses decrease.
|