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the portion of extracellular fluid that fills the microscopic spaces between the cells of tissues; the internal environment of the body.
one of many lymphatic vessels in villi of the intestines that absorb triglycerides and other lipids from digested food
interacts with cardiovascular system but doesn't have a pump; consists of vessels, structures, organs that contain lymphatic tissue adn red bone marrow
closed-ended microscopic lymphatic vesel that begins in spaces between cells and converges with othe rlymphatic capillaries to form lymphatic vessels
fluid confined in lymphatic vessels and flowing through thelymphatic system until it is returned to the blood
red bone marrow
a highly vascularized connective tissue located in microscopic spaces between trabeculae of spongy bone tissue..... Site of T and B cells production******
A bilobed organ, located in the superior mediastinum posterior to the sternum and between the lungs, in which T cells develop immunocompetence
large mass of lymphatic tissue between the fundus of the stomach and the diaphragm that functions information of blood cells during early fetal development, phagocytosis of ruptured blood cells, and proliferation of B cells during immune responses
tonsils, adenoids & peyers patches
Tonsils-lingual and palentine associated in mouth area; peyer's patches-associated with digestive system; appendix-part of your lymphatic system
become able to carry out the processes of your antibody immune system, carry out adaptive immune resonse, receptors for specific antigen
a lymphocyte that becomes immunocompetent in the thymus and can differentiate into a helper T cell or a cytotoxic T cell, both of which frunction in cell-mediated immunity
follicular dendritic cells
derived from monocytes, and so named because they have long, branched projections that resemble the dendrites of a neuron, assist the maturation process. Educate T cells, positive selection.
a lymphocyte that can develop into a clone of antibody-producing plasma cells or memory cells when properly stimulated by a specific antigen
the process by which phagocytes ingest and destroy microbes, cell debris, and other foreign matter
a type of white blood cell that helps carry out cell-mediated and anti-body-mediated immune responses; found in blood and in lymphatic tissues
special class of migratory cell that processes and presents antigens to T cells during an immune response; APCs include macrophages, B cells, and dendritic cells, which are present in the skin, mucouse membranes, and lymph nodes
the portion of the spleent hat consists of venous sinuses filled with blood and thin plates of splenic tissue called splenic (billroths) cords
the state of being resistant to injury, particularly by poisons, foreign proteins, and invading pathogens
lymphocytes, macrohpages, and fibroblasts infected with viruses produce proteins called interferons, or IFNS. Once released by virus-infected cells, IFNs diffuse to uninfected neighboring cells, where they induce synthesis of antiviral proteins that interfere with viral replication. Do not prevent viruses from attachign to and penetrating host cells, they stop replication. Three types... alpha, beta, and gamma-IFN
specialized cells that perform phagocytosis, the ingestion of microbes or other particles such as cellular debris. Two types... neutrophils and macrophages.
natural killer cells (NK cells)
Nonspecific defense consists of natural killer cells and phagocytes. About 5-10% of lymphocytes in the blood are Natural Killer (NK) cells. Also present in the spleen, lymph nodes, and red bone marrow. Lack th emembrane molecules that identify B and T cells, but have the ability to kill a wide variety of infected body cells and certain tumor cells. Attack any body cells that display abnormal or unusual plasma membrane proteins
Some granules contain a protein called perforin that inserts into the plasma membrane of the target cell and creates channels (perforations) in the membrane. As a result, extracellular fluid flows into the target cell and the cell bursts.
programmed cell death; a normal type of cell death that removes unneeded cells during embryological development, regulates the number of cells in tissues, and eliminates many potentially dangerous cells such as cancer cells. During apoptosis, the DNA fragments, the nucleus condenses, mitochondira cease to function, and the cytoplasm shrinks, but the plasma membrane remains intact. Phagocytes engulf and digest the apoptotic cells, and an inflammatory response does not occur
Specialized cells that perform phagocytosis, the ingestion of microbes or other particles such as cellular debris. Two major types are neutrophils and macrophages.
the largest type of white blood cell, characterized by agranular cytoplasm; two types, wandering and fixed macrophages.
the taking in of food, liquids, or drugs, by mouth;;;; surround the microbe, pinch off the membrane, microbe is now inside the membrane which is external to the cell; now in vesicle in the cell
localized, protective response to tissue injury designed to destroy, dilute, or wall off teh infecting agent or injured tissue; characterized by redness, pain, heat, swelling, and sometimes loss of function
an increase in the size of the lumen of a blood vessel caused by relaxation of the smooth muscle in the wall of the vessel
an elevation in body temperature above the normal temp of 37* C due to a resetting of the hypothalamic thermostat
a substance that has immunogenicity (the ability to provoke and immune response) and reactivity (the ability to react with the antibodies or cells that result from the immune response); contraction of antibody generator
antibody-mediated immune response
B cells transform into plasma cells, which synthesize and secrete specific proteins called antibodies or immunoglobulins. A given antibody can bind to and inactivate a specific antigen. Helper T cells aid the immune responses of both cell-mediated and antibody-mediated immunity. Works mainly against extracellular pathogens, which include any viruses, bacteria, or fungi that are inbody fluids outside cells.
a protein produced by plasma cells in resonse to a specific antigen; the antibody combines with that antigen to neutralize, inhibit, or destroy it.
cell-mediated immune response
Cytotoxic T cells directly attack invading antigens. Particularly effective against 1) intracellular pathogens, which include any viruses, bacteria, or fungi that are inside cells; 2) some cancer cells; and 3) foreign tissue transplants. Always involves cells attacking cells.
molecules are built into the plasma membranes of all body cells except red blood cells; are on all of your body cells except red blood cells
molecules appear on the surface of antigen-presenting cells; only on antigen presenting cells
the ability to provoke an immune response by stimulating the production of specific antibodies, the proliferation of specific T cells, or both
the ability of the antigen to react specifically with the antibodies or cells it provoked
certain small parts of a large antigen molecule act as the triggers for immune responses. Most antigens have many epitopes, each of which induces production of a specific antibody or activates a specific T cell
hman immune system has ability to recognize and bind to at least a billion different epitopes.T and B cells can recognize and respond to the intruder are ready and waiting. Diversity of antigen receptors is result of shuffling and rearranging a few hundred versions of several small gene segments.
major histocompatibility complex antigens
surface proteins on white blood cells and other nucleated cells that are unique for each person (except for identical siblings); used to type tissues and help prevent rejection of transplanted tissues
human leukocyte antigens; AKA MHC; transmembrane glycoproteins b'c they were first identified on white blood cells.
pathways of antigen processing
B cells and T cells must recognize that a foreign antigen is present. B cells recognize and bind to antigens in lymph, interstitial fluid, or blood plasma. T cells ONLY recognize fragments of antigenic proteins that are processed and presented in a certain way. In antigen processing, antigenic proteins are broken down into peptide fragments that then associate with MHC molecules. Next the antigen-MHC complex is inserted into the plasma membrane of a body cell. The insertion of the complex into the plasma membrane is called antigen presentation. When a peptide fragment comes from a self-protein, T cells ignore teh antigen-MHC complex. However, if the peptide fragment comes from a foreign protein, T cells recognize the antigen-MHC complex as an intruder, and an immune response takes place. AHHHHHHHH! Processing of exogenous antigens and endogenous antigens. pg. 850 Exogenous antigen--> phagocytosis or endocytosis of antigen--> digestion of antigen into peptide fragments -->synthesis of MHC-II molecules -->packaging of MHC-II molecules into a vesicle--> vesicles containing antigen peptide fragments and MHC-II molecules fuse--> antigen peptide fragments bind to MHC-II molecules--> vesicle undergoes exocytosis and antigen--MHC-II complexes are inserted into plasma membrane ::::: Endogenous antigens-->digestion of antigen into peptide fragments-->synthesis of MHC-I molecules-->antigen peptide fragments bind to MHC-I molecules--> packaging of antigen-MHC-I molecules into a vesicle--> vesicle undergoes exocytosis and antigen-MHC-I complexes are inserted into plasma membrane--> infected body cells present endogenous antigens inassociation with MHC-I molecules the MHC-I cells are then taken out by cytotoxic T cells
aka CD4 T cells; in addition to antigen receptors, their plasma membranes include a protein called CD4. activation of Helper T cell must have macrophage (has undergone phagocytosis and has MHC proteins and what it does isholding otu digested bits (epitopes) of antigen)
going to recognize things without the help of a helper T, Helper T lets cytotoxic T know what it is looking for; will kill cells that are other or have been invaded by other
cytotoxic T cells
aka CD8 T cells because their plasma membranes not only ontain antigen receptors but also a protein known as CD8.
helper T cell
recognize exogenous antigen fragments associated with major histocompatibility complex class II molecules at the surface of an APC. Costimulation occurs and helper T cell becomes activated.
memory Tc cells
do not attack infected body cells. Instead, they can quickly proliferate and differentiate into more active cytotoxic T cells and more memory cytotoxic T cells if the same antigen enters the body at a future time
recognition and co-stimulation must be present to activate and clonal selection of a helper T cell
memory T4 cells
of a helper T cell clone are not active cells. HOwever, if the same antigen enters the body again in the future, memory helper T cells can quickly proliferate and differentiate into more active helper T cells and more memory helper T cells
memory B cells
do not secrete antibodies. Instead, they can quickly proliferate and differentiate into more plasma cells and more membory B cells should the same antigen reappear at a future date
a protein produced by plasma cells in response to a specific antigen, the antibody combines w/ that antigen to neutralize, inhibit, or destroy it.
Antibodies are globulins; Most contain four polypeptide chains. Two of the chains are identical to each other and are called heavy chains; the two other chains are also identical to each other are light chains; A disulfide bond holds each light chain toa heavy chain.
antibodies belong toa group of glycoproteins called globulins and are known as immunoglobulins
an antibody synthesized by plasma cells derived from B lymphocytes in resopnse to the introduction of an antigen. Immunoglobulins are divided into five kinds (IgG, IgM, IgA, IgD, and IgE)
2 heavy and 2 light chains
2 heavy chains are identical to each other and consist of 450 amino acids. Short carbohydrate chains are attached to each heavy polypeptide chain. Light chains each consist of about 220 amino acids. Held together by a disulfide bond
Tips of the H and L chains. constitute the antigen-binding site. Different for each kind of antibody, is the part of the antibody that recognizes and attaches specifically to a particular antigen.
remainder of each H and L chain, is nearly the same in all antibodies of the same class and is responsible for the type of antigen-antibody reaction that occurs.l H chain distinguishes five different classes. Each has a specific biological role and structure.
antigen binding sites
are made up of the variable regions of the H and L chains. recognizes and attaches specifically to a particular antigen
neutralization of antigen
The reactinoof antibody with antigen blocks or neutralizes some bacterial toxins and prevents attachment of some viruses to body cells
complement proteins destroy microbes by causing phagocytosis, cytolysis, and inflammation; also prevent excessive damage to body tissues. Act in a cascade. With each succeeding reacdtion, more and more product is formed so that the net effect is amplified many times.
is due to the presence of long-lasting antibodies and very long-lived lymphocytes that arise during clonal selection of antigen-stimulated B cells and T cells. A hallmark of immune resopnses is memory for specific antigens that have triggered immune responses in the past.
primary immune response
After an initial contact with an antigen, no antibodies are present for a period of several days. Then a slow rise of the antibody titer occurs, first IgM and then IgG, followed by a gradual decline in antibody titer.
secondary immune response
memory cells may remain for decades. Every new encounter w/ the same antigen results in a rapid proliferation of memory cells. After subsequent encounters, the antibody titer is far greater than during a primary response and consists mainly of IgG antibodies. This accelerated, more intense response is called the secondary response. Antibodies have an even higher affinity for the antigen than those produced during a primary response, and have more success disposing of it.
how does the lymphatic system contribute to homeostasis
draining interstitial fluid as well as providing the mechanisms for defense against disease
describe nonspecific resistance to disease and how it differs from specific resistance or immunity
nonspecific-defenses present at birth; always present and aailable t provide rpaid responses to protect us against disease; doesn't involve specific recognition of a microbe and acts against all microbes in the same way; doesn't have a memory component; represent immunity's early warning system and designed to prevent microbes from gaining access into the body and eliminate those who do....... adaptive (specific) defenses that involve specific recognition of a microbe once it has breached the innate immunity defenses. Based on a specific response to a specific microbe; that is, adapts or adjusts to handle a specific microbe. Slower to respond, has a memory component. INvolves T lymphocytes and B lymphocytes
how are cell-mediated immunity and antibody-mediated immunity connected
*** co-stimulation by helper T cells help to activate b cells in the antibody-mediated immunity
what is the importance of specificity in the cell mediated immune response and in the antibody mediated response
describe the functions of the lymphatic system
Drains excess interstitial fluid; Transports dietary lipids; Carries out immune responses
describe the organs and parts of the lymphatic system and their respective functions
primary organs are teh sites where stem cells divide and becom eimmunocompetent. They include the red bone marrow and the thymus. Secondary lymphatic organs and tissues are teh sites where most immune responses occur. They include lymph nodes, the spleen, and lymphatic nodules.
describe lymphatic vessels and lymphatic circulation
vessels begin as capillaries. they are closed at one end. Veins have thinner walls and more valves. Lymph flows through lymph nodes, encapsulated bena-shaped organs consisting of masses of B cells and T cells. :::::: Capillary (reabsorption) plasma (filtration), Interstitial tissue (interstitial fluid (85% back as plasma)(15% as lymph)) Lymphatic capillary (fluid goes in but not out, lymph) Region of greater pressure to lower pressure
explain the routes for drainage of lymph from lymph trunks into the right lymphatic duct and the left subclavian vein
Right lymphatic duct is 1.2 cm long and receives lymph from the right jugular, right subclavian, and right bronchomediastinal trunks. Receives lymph from the upper right side of the body. From the right lymphatic duct, lymph drains into venous blood at the junction of the right internal jugular and right subclavian veins. Left subclavian vein .... The thoracic duct in turn drains lymph into venous blood at the left internal jugular and left subclavian veins.... The thoracic duct (left lymphatic duct) is about 38-45 cm long and begins as a dilation called the cisterna chyli anterior to the second lumbar vertebra. It is the main return of lymph to the blood. The cisterna chyli receives lymph from the right and left lumbar trunks and from the intestinal trunk. IN the neck, the thoracic duct also receives lymph from the left jugular, left subclavian, and left bronchomediastinal trunks. It receives lymph from the left side of the head, neck, and chest, the left upper limb, and the entire body inferior to the ribs
where do stem cells divide and become immunocompetent
T cells in the thymus B cells in the red bone marrow; primary lymphatic organs
where do immune responses occur
secondary lymphatic organs and tissues; are the sites where most immune responses occur. Include lymph nodes, the spleen, and lyphatic nodules. Thymus, lymph nodes, and spleen are considere organs b'c each is surrounded by a connective tissue capsule; lymphatic nodules, in contrast, are not considered organs b'c they lack a capsule
describe the events that occur in and the function of the primary lymphatic organs
sites wehre stem cells divid and become immunocompetent, that is, capable of mounting an immune response. organs are red bone marrow and thymus
describe the event that occurs in adn the function of secondary lymphatic organs and tissues
are the sites where most immune responses occur. Include lymph nodes, the spleen, and lyphatic nodules. Thymus, lymph nodes, and spleen are considere organs b'c each is surrounded by a connective tissue capsule; lymphatic nodules, in contrast, are not considered organs b'c they lack a capsule
describe and explain the structures, parts and functions involved in nonspecific resistance
innate immunity involves first and second lines of defenses. First line of defense is one you are born with and not for a specific organism they include : skin and mucous membranes (reproductive tract, digestive tract and respiratory tract) Fluids (saliva, lysozyme and other enzymes) CHemicals (lysozyme-recognizes bacteria, and drills a hole in the wall and then the bacteria is toast) also include cellular defenses (pluripotent stem cells in bone marrow, ganulocytes have short term memory for getting rid of invaders,, B&T lymphocytes and NK cells. SECOND line of defenses include antimicrobial substances (interferons- chemical that are produced by lymphocytes, macrophages, and fibroblasts when infected by viruses, secrete in response to a cell that has been infected by a virus, Complement proteins- series of proteins in the blood, in the plasma membrane, what they do is they complement or enhance the immune response and cause cytolysis of certain microbes and contribute to inflammation, enhance immune resonse, anti-bacteria, help to drill a hole, IRON-binding proteins- necessary for life, siderophores, proteins designed to hold onto iron, AMPs-short small peptiedes, attract dendritic cells and mast cells, INTERNAL defenses AHHHHH PG 846 table 22.1
describe the properties of natural killer cells
5-10% of lymphocytes in the blood are NK cells. They are present in the spleen, lymph nodes, and red bone marrow. Lack the membrane molecules that identify B and T cells but have the ability to kill a wide variety of infected body cells and certain tumor cells. Attack any body cells that display abnormal or unusual plasma membrane proteins. Secrete perforin that inserts into the plasma membrane of the target cell and creates channels in the membrane
describe the properties of phagocytes
are specialized cells that perform phagocytosis. Two types macrophages and neutrophils. When infection occurs, migrate to the area, and develop into actively phagocytic macrohpages. They are cell eating cells. Have properties of chemotaxis, adherence, ingestion, digestion, and killing
describe, in sequential order, the steps involved in phagocytosis
1) chemotaxis-movement in response to a chemical signal 2) adherence-sticking together of two things which aren't the same 3)ingestion- surround the microbe, pinch off the membrane, microbe is now inside the membrane which is external to the cell; now in vesicle in the cell 4) digestion-lysosome has digestive enzymes that which the membranes of the vesicle and lysozyme come together to form a large vesicle. Release enzymes, digest and kill 5) killing- phagolysosome becomes a residual body and can no longer harm anything
describe process of and the three stages of inflammation
a nonspecific, defensive response of the body to tissue damage. Four characteristic signs and symptoms of inflammation are redness, pain, heat, and swelling. Can also cause loss of function in the injured area. Inflammation is an attempt to dispose of microbes, toxins, or foreign material at the site of injury, to preven their spread to other tissues, and to prepare the site for tissue repair in an attempt to restore tissue homeostasis. The three stages are 1_ vasodilation and increased permeability of blood vessels 2) emigration(movement) of phagocytes from the blood into interstitial fluid, and ultimately, 3) tissue repair
what is specific resistance and immunity? what benefits does it provide for the body
Ability of the body to defend itself against specific invading agents such as bacteria, toxins, viruses, and foreign tissues is specific immunity (adaptive). 1) specificity for particular foreign molecules(antigens), which also involves distinguishing self from nonself molecules and 2) memory for most previous encountered antigens so that a second encounter prompts an even more rapid and vigorous response.
what are antigens
foreign molecules.... antibody generator.... when recognized by body immune system will stimulate the generation of T and B cells
describe the cell-mediated immune response
begins with activation of a small number of T cells be a specific antigen. Once a T cell has been activated, it undergoes clonal selection (a lymphocyte proliferates and differentiates in response to a specific antigen) The result of clonal selection is the formation of a clone of cells that can recognize the sameantigen as the original lymphocyte. Some of the cells of a T cell clone become effector cells, while other cells of the clone become memory cells. Th eeffector cells of a T cell clone carry out immune responses that ultimately result in elimination of the intruder.
describe the antibody-mediated immune response
Body contains millions of B cells capable of responding to a specific antigen. Cytotoxic T cells leave lymphatic tissues to seek out and destroy a foreign antigen, but B cells stay put. In the presence of a foreign atnigen, a specific B cell in a lymph node, the spleen, or mucosa-associated lymphatic tissue becomes activated. Then it undergoes clonal selection, forming a clone of plasma cells and memory cells. Plasma cells are the effector cells of a B cell clone; they secrete specific antibodies, which in turn circulate in the lymph and blood to reach the site of invasion
describe the required characteristics to be considered an antigen
Antigens are anti-body generating. THey must have immunogenicity (turns on, stimulates, get ready to go the antibody immune system) reactivity (has something to do w/ the process that not all organisms in the body can stimulate the process as well as others, depends on the ability to stimulate the antibody immune system) epitope or antigenic determinant (proteins will have specific shape, involves recognition of)
what is the significance of the diversity of antigen receptors
Major Histocompatibility complex antigens MHC or human leukocyte antigens (HLA) (function is to help a T cell recognize something is foreign or self) Class I MHC (are on all of your body cells except red blood cells CLASS II MHC (only on antigen presenting cells)
what are major histocompatibility complex antigens, what is their purpose and where do they occur
they occur on MHC-I on all of your body's cells and MHC-II on antigen presenting cells; their purpose to help identify good and bad cells
why is recognition of a foreign antigen important
for an immune response to occur, B cells and T cells must recognize that a foreign antigen is present. B cells can recognize and bind to antigens in lymph, interstitial fluid or blood plasma. T cells only recognize fragments of antigenic proteins that are processed and presented in a certain way.
describe the activation, proliferation, and differentiation of T cells
A T cell becomes activate donly if it binds to the foreign antigen and at the same time receives a second signal, a process known as costimulation. Most that display CD4 turn into helper T cells, also known as CD4 T cells. Inactive helper T cells recognize exogenous antigen fragments associated with major histocompatibility complex class II molecules at the surface of an APC. Then undergoes clonal selection to make active helper T cells and memory helper T cells. Active helper T cells start secreting a variety of cytokines. Memory helper T cells are not active, in the future memory helper T's can quickly proliferate and differentiate into more active helper T cells and more memory helper T cells.CD8 or cytotoxic T cells recognize foreign antigens combined with major histocompatibility complex Class I molecules on the surface of body cells infected by microbes, some tumor cells, and cell sof a tissue transplant.
what are antibodies
can combine specifically with the epitope on the antigen that triggered its production.
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