All Free Pathology MCQs with Answers

• A. Foreign body reaction
• B. Humoral
• C. Cell mediated
• D. None of the above

Explanation: Tuberculosis is controlled mainly by cell-mediated immunity, especially Th1 cells activating macrophages through interferon-γ.

• A. Intermediate leprosy
• B. Tuberculoid leprosy
• C. Borderline lepromatous leprosy
• D. Lepromatous leprosy

Explanation: Virchow cells are lipid-laden foamy macrophages packed with Mycobacterium leprae, a hallmark of lepromatous leprosy.

• A. Systemic arthus reaction
• B. An anaphylactic shock
• C. A transplant immunity
• D. None of the above

Explanation: Serum sickness is a type III hypersensitivity reaction caused by circulating immune complexes, classically described as a systemic Arthus…

• A. Membrane attack complex killing
• B. Zipper killing
• C. Oxidative and non-oxidative killing
• D. Chemotaxis

Explanation: Phagocytes destroy ingested bacteria through oxidative mechanisms, such as reactive oxygen species and myeloperoxidase, and non-oxidative…

• A. Monocytes
• B. Plasma cells
• C. Eosinophils
• D. Neutrophils

Explanation: Neutrophils are the predominant early leukocytes in acute inflammation and usually arrive within the first 24 hours.

• A. C3a, C5a
• B. C3b, C5a
• C. C2, C3
• D. C3b, C5b

Explanation: C3a and C5a are anaphylatoxins because they trigger mast-cell degranulation and increase vascular permeability.

• A. Kupffer cells in liver
• B. All of the above
• C. Histiocytes in connective tissues
• D. Microglial cells in nervous system

Explanation: Macrophages have different names according to their tissue location: Kupffer cells in the liver, microglia in the nervous system and…

• A. Plasma cells
• B. Macrophages
• C. PMN's
• D. Lymphocytes

Explanation: Chronic inflammation is dominated by macrophages, lymphocytes and plasma cells.

• A. It has a specific gravity of 1.018
• B. It is mucinous in consistencyOrder DNA Kits
• C. It has more than 3% proteins
• D. It has a low fibrin content

Explanation: Exudates are protein-rich inflammatory fluids, usually with specific gravity above about 1.018 and enough fibrinogen to form fibrin.

• A. Inhibits of B-lymphocytes
• B. Stimulation of T-lymphocytes
• C. Inhibits the chemotaxis of neutrophils and macrophages
• D. Decreases firbroblast and bone resorption activity

Explanation: IL-1, released mainly by activated macrophages, promotes T-cell activation and contributes to fever and acute-phase responses.

• A. Neutrophils
• B. Eosinophils
• C. Plasma cells
• D. Normoblats

Explanation: Plasma cells are much more typical of chronic inflammation because they represent differentiated, antibody-secreting B cells.

• A. Exudation
• B. Congestion
• C. Transudation
• D. Proliferation

Explanation: Granulomatous inflammation is a chronic proliferative response dominated by activated macrophages, epithelioid cells and giant cells.

• A. Low protein content
• B. Associated inflammatory conditions
• C. Tendency to clot
• D. Specific gravity of above 1.018

Explanation: Transudate forms mainly from altered hydrostatic or oncotic pressure without substantial inflammation, so it contains little protein.

• A. Leukocyte
• B. Mast cell
• C. Marcophage
• D. Fibroblast

Explanation: Mast cells store histamine, a vasoactive amine that rapidly produces arteriolar vasodilatation and increased venular permeability.

• A. Monocytes
• B. Plasma cells
• C. Neutrophils
• D. Basophils

Explanation: Neutrophils are the dominant early leukocytes recruited during acute inflammation, usually reaching the focus within the first 24 hours.

• A. Plasma cells
• B. Lymphocytes
• C. Monocytes
• D. Mast cells

Explanation: The vasoactive amine histamine is stored chiefly in mast cells, as well as basophils and platelets, and causes early vasodilatation and…

• A. Opsonisation
• B. Dilatation of blood vessels
• C. Pain
• D. Smooth muscle contraction

Explanation: Bradykinin causes arteriolar dilatation, pain, and contraction of some smooth muscle, but it does not opsonise microbes.

• A. It is associated with many types of severe inflammation
• B. It has low protein content
• C. It has fibrin precipitates
• D. It induces connective tissue organization

Explanation: Fibrinous exudate is protein-rich because leaked fibrinogen polymerises into fibrin at the inflammatory site; it may later undergo…

• A. Vasodilation
• B. Stasis of blood
• C. Decreased hydrostatic pressure
• D. Increased vascular permeability

Explanation: Acute inflammation produces vasodilatation, increased permeability, and slowing of blood flow with stasis; hydrostatic pressure generally…

• A. Presence of acute inflammation
• B. Formation of caseous pus with signs of acute inflammation
• C. Infected cyst
• D. Formation of caseous pus without signs of acute inflammation

Explanation: A cold abscess is typically a tuberculous collection of caseous material that develops without the marked heat, redness, pain, and acute…