White blood cells

• What is one of the functions of the circulatory system in humans?

  To transport substances
• What are the main components of the circulatory system?

  • The heart
  • Blood vessels
  • Blood
  • White blood cells
• What percentage of white blood cells are phagocytes?

  About 70 percent
• What is the role of phagocytes in the immune system?

  To engulf and destroy unwanted microorganisms
• What process do phagocytes use to destroy microorganisms?

  Phagocytosis
• What is the immune system's primary function?

  To prevent disease
• What percentage of white blood cells are lymphocytes?

  About 25 percent
• What do lymphocytes produce when a foreign body enters the body?

  Antibodies
• What are platelets produced by?

  Giant cells in the bone marrow
• How do platelets stop bleeding?

  • They stick to breaks in blood vessels
  • They secrete proteins that trigger blood clotting
• What are blood products?

  Components of blood given to a patient by transfusion
• What are the components of blood products?

  • Red blood cells
  • Platelets
  • Plasma
  • Antibodies
• Why are blood products screened before transfusion?

  To check for infectious agents and blood group compatibility
• What must blood for transfusion be compatible with?

  The patient's blood
• Why are white blood cells often removed before a transfusion?

  To reduce the risk of infections or immune reactions
• What is the typical size of many types of blood cells?

  10 μm or less
• What is a commonly-used stain for examining blood cells?

  Giemsa stain
• What colors do Giemsa stain different blood components?

  • Red blood cells: pink
  • Platelets: pale pink
  • White blood cell cytoplasm: pale blue
  • White blood cell nuclei: magenta
• What is the role of the circulatory system in multicellular organisms?

  To supply cells and remove waste products
• What is the significance of blood transfusion in modern medicine?

  It allows patients to receive necessary blood components
• Why is it important to match blood groups in transfusions?

  To prevent adverse reactions in patients
• What is the function of antibodies in the immune system?

  To attack foreign organisms that enter the body
• How does the immune system prevent disease?

  By defending against foreign bodies and pathogens