BIOL 2300 – Host Defenses & Immunity Review (2025/2026) | 100+ Verified Q&A | Innate vs Adaptive, Inflammation, Antibodies, Hypersensitivity, T-Cells

This 2025/2026 BIOL 2300 Host Defenses review includes over 100 verified exam questions and answers designed to master the immune system’s two key branches—innate and adaptive immunity. Organized in a Q&A format, it simplifies complex immunology concepts into clear, exam-ready responses ideal for test prep, study groups, and individual review. Topics covered in detail include: Innate Immunity: Physical and chemical barriers, phagocytosis, inflammation, mediators (e.g., histamine, prostaglandins), and cellular responders (e.g., neutrophils, mast cells) Adaptive Immunity: T-cell and B-cell activation, immune memory, specificity, tolerance, and the four types of adaptive responses (natural active, natural passive, artificial active, artificial passive) Antibody structure and function: Immunoglobulin types (IgG, IgM, IgA, IgD, IgE), antibody-mediated defense mechanisms such as neutralization, agglutination, opsonization, and complement activation Cell-Mediated Immunity: CD4+ helper T-cells, CD8+ cytotoxic T-cells, MHC class I and II restriction, and antigen recognition Hypersensitivity Reactions: Types I–IV including anaphylaxis, cytolysis, immune complex formation, and delayed-type hypersensitivity Additional insights into immune regulation, class switching, and immunological memory This guide is especially helpful for exams covering immunology modules within microbiology, general biology, and health science programs. Relevant for: Courses: BIOL 2300, Immunology, Microbiology, Pathophysiology, Allied Health Biology Students: Nursing students, Pre-med students, Physician Assistant (PA) students, Health Sciences majors, Clinical Lab Tech students Keywords: innate immunity, adaptive immunity, inflammation, histamine, prostaglandins, phagocytosis, neutrophils, mast cells, lymphocytes, T-cells, B-cells, antigen, antibody, immunoglobulin, IgG, IgA, IgM, IgD, IgE, humoral immunity, cell-mediated immunity, MHC I, MHC II, CD4, CD8, hypersensitivity, immune memory, class switching, opsonization, complement system, host defenses, BIOL 2300 immunity