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PA13.{1,3} | Hematopoiesis & Blood Specimen Basics — Worksheet
CLINICAL SCENARIO
A structured written worksheet that takes you from the bone marrow niche to the blood collection tube — tracing lineage commitment, growth factor signalling, and the specimen-quality decisions that make or break a pathology result.
Instructions
Complete all five sections in sequence. Hand-draw Sections 1 and any diagrams requested; scan or photograph neatly and include in your submission PDF. Type your written responses (Sections 2–5) in a word processor, then combine with scanned diagrams into a single PDF. Target 1500–2000 typed words plus 2 labelled hand-drawn diagrams. Submit via Canvas by the date shown on the course page. Late submissions lose 10% per day. Include your name, roll number, and date on every page.
Length: 1500–2000 typed words total + 2 hand-drawn diagrams (Section 1 mandatory; an optional tube-system schematic in Section 3 is encouraged but not graded separately)
What to Submit
Section 1: Hematopoiesis Hierarchy Diagram (hand-drawn)
Section 2: Extramedullary Haematopoiesis (EMH) Scenario Analysis
Section 3: Blood Collection Tube Identification — Table Completion
Section 4: Wrong-Tube Troubleshooting Cases
Section 5: Reflection — Specimen Quality as the Silent Half of Pathology
Grading Rubric — Worksheet Assessment Rubric
| Criterion | Points | Full-marks descriptor |
|---|---|---|
| Hematopoiesis hierarchy and growth factor annotation (PA13.1) | 5 pts | Exceeds: All major lineage branches present and correctly labelled; growth factors (EPO, TPO, G-CSF, SCF, IL-3, IL-7) placed at correct branch points; niche annotation (endosteal/vascular) included; diagram is clear and self-explanatory. |
| EMH conceptual understanding — mechanism and clinical linkage (PA13.1) | 5 pts | Exceeds: Correctly identifies chronic haemolytic anaemia → tissue hypoxia → EPO surge → progenitor mobilisation; explains marrow insufficiency specific to thalassaemia (ineffective erythropoiesis); names liver, spleen, and skull diploe as EMH sites and links each to a clinical sign; reasoning is precise and flows logically. |
| Tube-anticoagulant mapping accuracy — table completion (PA13.3) | 5 pts | Exceeds: All 6 tubes correctly completed; anticoagulant, mechanism, primary test(s), and specific wrong-tube consequence all present and accurate; consequences are quantitatively or analytically specific (e.g. 'EDTA chelates calcium → PT unmeasurable' rather than 'result affected'). |
| Wrong-tube troubleshooting reasoning — analytical logic and corrective action (PA13.3) | 5 pts | Exceeds: All three scenarios correctly analysed; Scenario A correctly identifies EDTA's calcium chelation invalidating coagulation factors; Scenario B explains heparin interferes with WBC differential staining and platelet clumping artifacts; Scenario C explains underfilling dilutes citrate ratio → over-anticoagulation → falsely prolonged clotting times → sample must be rejected. Corrective action for each is appropriate and specific. |
| Reflection — depth of understanding and professional communication (PA13.3) | 3 pts | Exceeds: Reflection makes a patient-safety argument (not just a procedural one); uses a specific, accurate example from this week's content; tone is collegial and non-condescending; approximately 100 words; demonstrates genuine insight beyond rote repetition of lecture points. |