Haematology

• What are the main components of blood?

  Plasma, RBC, WBC, Platelets
• What percentage of body weight does blood constitute?

  8%
• What is the protein composition of plasma?

  7% proteins including albumins, globulins, fibrinogen
• What is the percentage of albumins in plasma proteins?

  57-60%
• What is the percentage of globulins in plasma proteins?

  38%
• What is the percentage of fibrinogen in plasma proteins?

  4%
• What is the water composition of plasma?

  92% water
• What are the formed elements in blood?

  Platelets, erythrocytes, leukocytes
• What is the normal range of platelets per cubic mm?

  140-340,000
• What is the normal range of erythrocytes per cubic mm?

  4.2-6.2 million
• What is the normal range of leukocytes per cubic mm?

  5-10,000
• What is the first line of defense in leukocytes?

  Neutrophils 40-60%
• What percentage of lymphocytes are B+T cells?

  20-40%
• What is the percentage of monocytes in leukocytes?

  2-8%
• What is the percentage of eosinophils in leukocytes?

  2-4%
• What is the percentage of basophils in leukocytes?

  0.5-1%
• What is haematopoiesis?

  Production of blood cells in bone marrow
• What are the types of stem cells involved in blood cell production?

  Myeloid stem cells, lymphoid stem cells
• What is the function of RBCs?

  Measure blood's oxygen capacity
• Why do RBCs have a concave shape?

  To provide a larger surface area
• How long do RBCs last in circulation?

  Last 3 months
• Where are RBCs destroyed?

  In the liver by macrophages
• What happens to hemoglobin when RBCs are digested?

  It breaks down into globin and heme
• What is produced from the breakdown of heme?

  Iron and biliverdin
• What happens to bilirubin after its formation?

  Bilirubin is excreted
• What is the structure of hemoglobin?

  Made of 4 globin chains, each with heme
• How many alpha and beta chains are in hemoglobin?

  2 alpha and 2 beta chains
• What gives hemoglobin its red color?

  Iron in the heme molecule
• What are the main proteins found in plasma?

  • Albumins
  • Globulins
  • Fibrinogen
• What are the steps of haemostasis?

  1. Blood vessel spasm (vasospasm)
  2. Platelet plug formation
  3. Blood coagulation
• What triggers platelet plug formation?

  Exposed collagen fibers
• What is the duration of vasospasm?

  Lasts 30 minutes
• What are the two pathways of blood coagulation?

  • Intrinsic pathway: exposure to collagen
  • Extrinsic pathway: triggered by tissue factor
• What is the role of factor 10 in coagulation?

  Activates prothrombin to thrombin
• What does thrombin convert fibrinogen into?

  Fibrin, which forms a mesh
• What is the purpose of negative feedback in clotting?

  To prevent excessive clotting
• What are the blood groups and their antigens?

  • A: A antigen
  • B: B antigen
  • O: No antigens
  • AB: A and B antigens
• What antibodies are present in blood group A?

  Anti-B antibodies
• Which blood group can give to anyone?

  Type O
• Which blood group can receive any blood type?

  Type AB