Blood and Gaseous Exchange

• What is the pH range of human blood?

  7.35 - 7.45
• Why is the regulation of pH important in blood?

  Small changes can be detrimental to health
• What is acidosis?

  Condition of low blood pH
• What is alkalosis?

  Condition of high blood pH
• What regulates water in blood plasma?

  • Serum albumin in plasma
  • Balances osmotic concentration
  • Maintains oncotic pressure
• What factors affect blood pressure?

  Hormones and neural signals from the brain
• How does vasoconstriction affect blood pressure?

  It decreases arterial diameter, increasing blood pressure
• What is the "fight or flight" response in relation to blood pressure?

  It conserves blood to main organs
• What is the hepatic portal circulation?

  • Blood from stomach and intestine
  • Goes to liver via hepatic portal vein
  • Rich in nutrients and chemicals
• What is the function of the liver in blood circulation?

  Removes toxins and stores sugar
• What percentage of blood volume is plasma?

  55%
• What are the components of blood?

  • Plasma
  • Red blood cells (RBC)
  • White blood cells (WBC)
  • Platelets
• What is the fluid matrix of blood called?

  Plasma
• What is the main solvent in plasma?

  Water (92%)
• What are the main plasma proteins?

  Albumin, globulin, and fibrinogen
• What happens if an anticoagulant is not added to blood collection?

  Fibrinogen will coagulate blood cells
• What is haematopoiesis?

  • Development of blood cells
  • Occurs in bone marrow
  • Stem cells differentiate into blood cells
• What types of stem cells are generated in haematopoiesis?

  Lymphoid and myeloid
• What do erythrocytes primarily carry?

  Oxygen
• Where are erythrocytes produced?

  Red bone marrow
• How many red blood cells are produced per second?

  2,000,000
• What is the typical count of red blood cells in 1 ml of blood?

  5,000,000
• What is the structure of erythrocytes?

  Biconcave discs with no nucleus or mitochondria
• What is the role of hemoglobin in erythrocytes?

  Transport of oxygen
• How many polypeptide chains does hemoglobin have?

  Four polypeptide chains
• What is the significance of the hem group in hemoglobin?

  Each can carry 4 x O2
• What happens to hemoglobin in the lungs?

  It joins to O2 to form oxyhemoglobin
• What mediates the affinity of hemoglobin for O2?

  Partial pressure of oxygen and carbon dioxide
• What is the Bohr Effect?

  Lowered pH decreases hemoglobin's affinity for O2
• What are the structural features of erythrocytes and their functions?

  • Small size: Rapid uptake of oxygen
  • Biconcave discs: High surface area to volume ratio
  • Large amounts of hemoglobin: Efficient oxygen transport
  • No nucleus or mitochondria: More space for hemoglobin
• What are leucocytes also known as?

  White blood cells
• How many leucocytes are there compared to RBC?

  1:700
• What is the primary function of leucocytes?

  Specific roles in immunity
• What are the types of granular leukocytes?

  • Neutrophils: Phagocytic, ingest bacteria
  • Eosinophils: Detoxify foreign proteins, increase during allergies
  • Basophils: Release histamine and heparin
• What is the role of neutrophils?

  Ingest bacteria and clean up dead cells
• What do eosinophils do?

  Detoxify foreign proteins
• What do basophils release?

  Histamine and heparin
• What are the types of agranular leukocytes?

  • T-cells: Develop into macrophages
  • B-cells: Produce antibodies
  • Monocytes: Engulf pathogens and dead cells
• What are platelets also known as?

  Thrombocytes
• What is the primary function of platelets?

  Clotting and scab formation