A physician-validated, board-style question from the Active Transport QBank. Try it, then check the reasoning for every option.
A 31-year-old woman scrapes her finger on an exposed nail and sustains a minor laceration. Five minutes later, her finger is red, swollen, and painful. She has no past medical history and does not take any medications. She drinks socially with her friends and does not smoke. The inflammatory cell type most likely to be prominent in this patient's finger has which of the following characteristics?
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A
Dark histamine containing granulesIncorrect. Dark histamine-containing granules describe basophils and mast cells, which mediate immediate hypersensitivity reactions, not acute traumatic inflammation.
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B
Dramatically expanded endoplasmic reticulumIncorrect. Dramatically expanded rough ER describes plasma cells secreting antibodies — a chronic humoral response, not the first 5 minutes of injury.
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C
Large cell with amoeboid movementIncorrect. Large cells with amoeboid movement describe macrophages, which arrive after 24-48 hours, not within the first 5 minutes.
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D
Segmented nucleiCorrect. neutrophils with multilobed (segmented) nuclei are the predominant cells in the earliest phase of acute inflammation.
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E
Multilobed kidney-shaped nucleusIncorrect. A kidney-shaped (reniform) nucleus characterizes monocytes/macrophages, which migrate to inflammatory sites at 24-48 hours, not within the first 5 minutes when neutrophils predominate.
↑ Tap an answer to reveal the reasoning
Answer: D. An acute laceration with redness, swelling, and pain developing within 5 minutes is the very earliest phase of acute inflammation. The first cellular responders to acute tissue injury and bacterial contamination are neutrophils (polymorphonuclear leukocytes), which arrive at the site within minutes to hours via increased vascular permeability and chemotactic gradients (C5a, leukotriene B4, IL-8, bacterial products). The defining morphologic feature of neutrophils is their multilobed (segmented, typically 2-5 lobes) nucleus — hence the term polymorphonuclear.
Neutrophils phagocytose bacteria and debris using oxidative burst (NADPH oxidase generating superoxide and hypochlorous acid) and granule contents (myeloperoxidase, elastase, defensins). They predominate in the first 24-48 hours of acute inflammation.
Distractors describe other inflammatory cells: dark histamine granules describe basophils/mast cells (allergic/immediate hypersensitivity); dramatically expanded rough ER describes plasma cells producing antibodies (chronic/humoral immunity); large cells with amoeboid movement describe macrophages (later in inflammation, days 2-3 onward). The 5-minute timeline points unambiguously to neutrophils.
**Why each option:**
**A.** Dark histamine-containing granules describe basophils and mast cells, which mediate immediate hypersensitivity reactions, not acute traumatic inflammation.
**B.** Dramatically expanded rough ER describes plasma cells secreting antibodies — a chronic humoral response, not the first 5 minutes of injury.
**C.** Large cells with amoeboid movement describe macrophages, which arrive after 24-48 hours, not within the first 5 minutes.
**D.** Correct — neutrophils with multilobed (segmented) nuclei are the predominant cells in the earliest phase of acute inflammation.