PATH2220 Final Exam - Learning outcome- based Questions and Answers 2024

PATH2220 Final Exam - Learning outcome- based Questions and Answers 2024 define key terms associated with the pathological basis of disease such as disease, aetiology, pathogenesis - Answer- Disease = abnormal condition where normal function (homeostasis) of body part/organ is disturbed Aetiology = cause of disease/condition (inherited/acquired) Pathogenesis = manner of development of disease - cellular events / changes / reactions caused by aetiology that alter normal cellular processes describe the different methods used to recognise pathological features of disease (levels of examination) - Answer- -Macroscopic -Microscopic -Ultrastructural (sub-cellular - organelles; electron microscope) -Genetic / molecular (chromosomes, nucleic acid) -Functional (cellular function) describe the pathology testing cycle - Answer- 1. Pre-analytic - specimen checked against request form 2. Analytic / testing - sample processed, controls, audit 3. Post-analytic - pathologist validates results, reported back to requesting doctor, feedback demonstrate understanding of the different disciplines of pathology and the role they play in the diagnosis and classification of human disease - Answer- -Anatomical - histopathology, cytopathology, electron microscopy, molecular pathology -Chemical / biochemical -Haematology -Genetic -Immunology -Microbiology -Forensic view photographed microscopy slides and make a judgement about what type of sample is on the slide and how it might have been prepared (5 steps in preparing sample - blood vs cells vs tissue) - Answer- 1. Acquire sample: blood (venepuncture), cells (body fluids, FNA, tissue scrape), tissue (core biopsy, wide local excision, entire organ) 2. Process sample (if necessary) - blood (whole blood vs WBC prep), cells (concentration by centrifugation), tissue (fix in formalin & embed in wax, freeze) 3. Transfer to slide - blood (blood smear, cytospin if WBC), cells (smear, cytospin), tissues (cut with microtome / cryostat) 4. Stain - blood (Diff quik, Giemsa, wright), cells (Papanicolau), tissues (H&E, special stain, immunohistochemistry) 5. Analyse by microscopy choose appropriate preparation methods for different types of samples depending on the purpose for analysis - Answer- *See screenshots describe the composition and functions of blood - Answer- Components: cellular = erythrocytes, leukocytes (granulocytes, lymphocytes, monocytes), thrombocytes (cell fragments of megakaryotes), extracellular matrix = plasma *Serum = identical to plasma except no fibrinogen Functions of RBCs: transfer O2 from lungs to tissues / CO2 from tissues to lungs Functions of WBCs: respond to foreign substances, inflammatory & immune responses Functions of plasma: albumin (transport), antibodies (immune), fibrinogen (clotting) Functions of platelets: release serotonin - constricts BVs, stick to exposed collagen fibres on broken BVs - temporary plug, enmeshed in fibrin - healing recognise normal blood cells on photographed microscopy slides - Answer- -Erythrocyte - no nucleus, central area of pallor -Neutrophils - 3 lobes (most dominant WBC type) -Eosinophils - 2 lobes, orange/pink granules -Basophils - dark granules that hide nucleus (least dominant) -Lymphocytes - large round nucleus, no granules -Monocytes - horseshoe nucleus, largest cell -Thrombocytes - small fragments, no nucleus describe the role of stem cells and bone marrow in the production of blood - Answer- Haemopoiesis = production of blood cells Haemopoietic tissues = produce blood cells from stem cells (yolk sac in embryo - liver, spleen - bone marrow) Haemopoietic stem cells = stem cells that can only produce blood cells - Myeloid lineage: RBCs, platelets, mast cells, granulocytes, monocytes (macrophages / dendritic cells) - Lymphoid lineage: NK cells, T & B cells define anaemia and demonstrate understanding of the causes of anaemia - Answer- Anaemia = reduction in oxygen-transporting capacity (haemoglobin concentration) of blood - due to decreased RBC mass Symptoms: shortness of breath, organ failure, shock, pallor, fatigue 3 main causes: -Increased RBC destruction - hereditary / autoimmune haemolytic anaemia -Decreased RBC production - primary: aplastic anaemia (bone marrow failure), myelodysplasia (bone marrow dysfunction), secondary: iron deficiency anaemia, other nutrient deficiency, infection, drugs, leukaemia / metastasised cancer -Blood loss - haemorrhage describe features of anaemic conditions including, reduced and defective production, particularly iron deficiency; and increased destruction or loss, particularly haemolytic anaemia - Answer- Iron deficiency anaemia - dietary iron required for RBC production Without: -Area of central pallor increases = hypochromic -Smaller (low MCV) = microcytic Vit B12 deficiency - pernicious / megaloblastic anaem