| A | B |
|---|
| Node | filtering organ of the lymphatic system |
| Antibodies | proteins which are specific in the defense of the body; fight antigens |
| Leukocyte | white blood cell |
| Spleen | largest organ of the lymphatic system; gets rid of damaged or old red blood cells |
| Fever | elevated body temperature |
| Lymph | tissue fluid that is in the lymph vessels |
| autoimmunity | loss of the sense of "self" |
| tonsils | masses of tissue in the pharynx; one of the first lines of defense |
| allergy | an immune response to a non-harmful substance |
| lymphatic | system which returns tissue fluid to the circulatory system and defends the body against pathogens |
| antigens | substances that cause the body to produce antibodies |
| macrophages | white blood cells that destroy any foreign organism |
| B-cells | cells that form antibodies |
| cytotoxic T-cells | cells that produce cytotoxins |
| helper T-cells | cells that activate B-cells or T-cells |
| immunizations | exposure to infectous organisms to enable the body to prepare memory cells |
| AIDS | a disease that destroys helper T-cells |
| valve | A structure that keeps fluid flowing in a forward direction |
| vessel | A tube or duct to transport fluid. |
| lymph | The thin plasma like fluid that drains from the tissues and is transported in lymphatic vessels. |
| lymph node | A small mass of lymphoid tissue along the path of a lymphatic vessel that filters lymph. |
| thymus gland | A gland in the upper part of the chest beneath the sternum. It functions in immunity. |
