Anatomy Bowl Prep The Lymphatic and Immune System by Zachary Hale Know and understand these terms.

 The lymphatic system is our “safety net” also known as our immune system.  It is composed of vessels that help maintain fluid balance and lymphoid tissues that help protect the internal environment

 Understand how the different regions of the body are drained.  Understand the flow of lymph through lymph nodes  Understand the role of lymph nodes in microbial defense

 Lymph  Fluid in the tissue spaces that carries protein molecules and other substances back to the blood  Lymph Nodes  Bundles of cells along the lymphatic system that: ▪ Filters lymph ▪ Defends the body and houses WBC ▪ Has afferent and efferent vessels that allow lymph to flow in and out in one direction  Lymphatic Vessels  Permit only one way movement of lymph

 Interstitial fluid  Is the fluid that leaks out of the capillaries and in between tissues  Right Lymphatic Duct  Returns lymph to the heart from the right arm, right upper chest, and right side of the face  Thoracic Duct  Lymph from ¾ of the body return via the thoracic duct  Lacteals  Absorb fats from the villi of the small intestine and carries it through the lymphatic system

 As lymph flows from its origin in the tissue spaces toward the thoracic or right lymphatic ducts and then into the venous blood it is filtered by moving through lymph nodes  Lymph nodes are used for:  Biological filtration of the lymph and for defense  Fluid enters through the afferent side and leaves via the efferent side  Macrophages and WBC that reside in the lymph nodes filter and sample the blood ▪ If a pathogen is found it enables body to respond quickly!

 Know the basic roles in immunity of the different lymphatic organs: Thymus, Tonsils (3 types), Spleen  Define and study the difference between:  Nonspecific Immunity  Specific Immunity

 Thymus  Small lymphoid organ located in the mediastinum  Composed of lymphocytes in a unique epithelial meshwork  Is the site for T-cell maturation ▪ A WBC vital for defense ▪ T-cells develop under the influence of the hormone thymosin  Tonsils  Masses of lymphoid tissue  Are located in a protective ring under the mucous membranes of the mouth and back of the throat  Spleen  Largest lymphoid organ  Filters the blood

 Specific immunity  Includes protective mechanisms that confer very specific protection against certain types of pathogens  Involves memory and the ability to recognize and respond to particularly harmful substances  Nonspecific immunity  Is maintained by mechanisms that affect any irritant or abnormal substance that threatens the body  General protection!

 Antibodies  Complement Know how these proteins function to defend against invasion:

 Antibody:  Protein compounds that are normally present in the body  They bind to antigens (may be foreign proteins, most often molecules on the surface of things invading the body)  Complement proteins  Is the name used to describe 14 proteins normally present in an inactive state in the blood  Proteins are activated by exposure of complement- binding sites to antibodies  This results in the formation of a highly specialized antigen-antibody complex that targets foreign cells for destruction

 Phagocytes- cells that use phagocytosis to ingest foreign particles  Neutrophils  Monocytes  Macrophages  Lymphocytes  T-Lymphocytes ▪ Sensitized T cells- can kill invading cells or recruit macropahges  B-Lymphocytes ▪ Immature B cells ▪ Activated B cells ▪ Plasma cells – send huge amounts of antibodies into the blood ▪ Memory cells – wait in lymph nodes for second exposure to an antigen Know the basic function of each of these cell types and where they are formed:

 What is a disease process that attacks the immune system directly and how?

 HIV  Is a virus that directly attacks the body  The virus invades T-cells  Then uses the T-cell machinery to produce more copies of the virus  Eventually the T-cell is bombarded with new virus molecules and explodes releasing more virus molecules into the blood