| Term | Definition |
| Antimicrobials | Group of proteins that inhibit bacterial/viral growth |
| Interferon | A protein produced by a cell thats infected with a virus; diffused into other cells to prevent replication/spread of viruses |
| Complement | Group of inactive proteins that are found in plasma and activated by bacterial invasion; enhances body's immune responses |
| Transferrin | Inhibits bacterial growth by reducing available iron |
| Fever | Excessively high body temperature; inhibits bacterial growth; speeds up metabolism, which hastens repair actions |
| Inflammation | When cells or tissues are damages by chemicals, heat, or pathogens; redness, heat, swelling, pain |
| Vasodilation | Increases blood flow; increases blood vessel permeability |
| Increases vasodilation | Histamine, kinins (polypeptides, prostaglandins (lipids), leukotrienes, complements |
| Phagocyte migration | Relies on chemotaxis and diapedesis; blood accumulates and neutrophils and monocytes squeeze out of the blood vessel walls |
| Tissue repair | Phagocytes eventually die after their task complete (formation of pus); continues until pus is reabsorbed or leaks into a cavity |
| Abcesses | When pus cannot drain out of an area |
| Ulcer | When the layer of tissue over the pus becomes an open sore |
| Priming | Where the immune system recieves an intial exposure to a pathogen before it can defend itself from it at a later time |
| Lymphocytes | Developed from lymphoid cells in red bone marrow; carry out special immune responses |
| B cells | Lymphocytes that mature in red bone marrow |
| T cells | Lymphocytes that mature in the thymus |
| Antigen receptors | Surface proteins that B and T cells acquire through maturation that recognizes specific antigens |