2 Lesson ObjectivesUpon completion of this lesson, students should be able to …Identify and discuss the anatomy of the immune system.Discuss the functions of the immune system.Explain the immune system and its response.
3 Composition of the Immune System TissuesOrgansPhysiological processes that identify abnormal cellsForeign substancesForeign tissues, such as transplants
4 Structures Central to the Immune System Central lymphoid tissuebone marrow, thymusPeripheral lymphoid tissuelymph nodes, spleen, and mucus membranes
5 Critical Thinking Questions What is so critical about the immune system to one’s overall health?If one has a compromised immune system would that shorten the person’s life?
6 The Immune System throughout the body part of the lymphatic system subsystem of the CV systemPrimary fx is to defend against invasionPathogens (viruses, bacteria, and fungi)Immunosuppressants, medications, and stress can suppress system
9 Bone Marrow Contains stem cells that create all the cells Produces RBC’sWBC’sPlateletsB cellsNatural killer cells
10 Thymus Gland Located posterior to the sternum Manufactures infection-fighting T cellsHelps distinguish normal T cells from those that attack the bodyEnlarges during childhoodShrinks as we age
11 Peripheral Lymphatic System Consists of the lymph nodes, spleen, and other lymphoid tissue
12 Lymph Nodes Different sizes and shapes Most are bean-shaped, about 1 inch longCovered with a thick fibrous capsule
13 Two Parts of Lymph Nodes CortexPopulated mainly with lymphocytesMedullaPrimarily made up of macrophages
14 B Lymphocytes Responsible for circulating antibodies When an antigen enters the body,B lymphocytes rapidly undergo mitosis and divideThis produces a large quantity of an antibody
15 Spleen Located in the ULQ of the abdomen Lots of blood vessels Spleen’s blood vessels are lined with macrophagesswallow and digest debris in the bloodworn-out red blood cells and platelets15
16 Tonsils used to be removed when infected. Located in the depressionsof the throat and the pharynxFx -filter bacteriaaid in the formation of white blood cellsFactoid:Tonsils used to be removed when infected.16
18 The Immune SystemDefense against infectious organisms and pathogenic invadersImmune responsecells, tissues, and organs work together to attack pathogenwhite blood cells (WBCs), seek out and destroy harmful organisms
19 Phagocytes Phagocytes WBC that attacks the invading organism most common are neutrophils, which fight off bacteria
20 Lymphocytes Lymphocytes WBC allows the body to remember previous invading organismsOriginate in the bone marrowIf stays there, it matures into B cellsIf moves to the thymus gland, they mature into T cells
21 B and T Lymphocytes B lymphocytes Seek out invading organisms and send defenses to attach onto themT cellsDestroy the organisms that the B lymphocytes have id
22 Antigen Foreign substance that invades the body When an antigen is detected, several types of cells work together to recognize and respond to itThese cells trigger the B lymphocytes to produce antibodiesThis process is known as humoral immunity
23 Antibodies Specialized proteins that lock onto specific antigens ImmunoglobulinsAntibodies are found in blood, tissue fluids, and many secretions
24 B Cells of the Immune System Once antibodies have been produced, they remain in the bodyIf re-infected, the antibodies are already there to neutralize itantibodies can recognize an antigen and lock onto it, but are not capable of destroying it.That is the job of the T cells.
25 T Cellsdestroys antigens which have been tagged by antibodies
26 Immunity The body’s ability to defend itself against pathogens 3 Forms 26
27 Innate Immunity Born with innate, or natural, immunity Renders many of the viruses and bacteria incapable of harming infantProvided by :SkinMucous membranesMother
28 Active Immunityby infection or with a vaccineIs permanent ??
29 Types of Active Immunity Acquired active immunityexposed to a live pathogendevelops the diseaseand becomes immune (primary immune response)Artificially acquired active immunityinduced by a vaccine (antigen)stimulates a primary response against the antigenwithout causing symptoms of the disease
30 Passive Immunity“Borrowed” from another source and lasts for only a short timeAn inherited immunity to certain diseases
31 Medical SpecialistsAllergistImmunologistOncologist