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