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Question 320
Physiology → Haematology
Classification
Question
SSBAOptions
Explanation
Monocytes circulate before migrating into tissues and becoming macrophages. in chronic infections such as tuberculosis and leprosy, macrophage-lineage cells may form multinucleated giant cells.
Option Validity
A) Basophils are granulocytes containing coarse granules with histamine and heparin. They are not identified as precursors of tissue macrophages or multinucleated giant cells.
C) Eosinophils are associated particularly with parasitic infestation, allergy and mucosal immunity. does not describe them as precursors of giant cells.
D) B lymphocytes mediate humoral immunity and are associated with immunoglobulin production. They do not undergo the monocyte-to-macrophage transition described here.
E) Neutrophils are important bacterial phagocytes and are abundant in pus. The tissue macrophage and giant-cell lineage described in originates from monocytes.
Further Reading
Saxena. Textbook for MRCOG-1. Physiology - Haematology - Monocytes, p.70.