blood vessels, blood tissue and lymph

• What are the three components of blood?

  Red cells, white cells, and platelets
• How is tissue fluid formed from blood plasma?

  By pressure filtration through capillary walls
• What is the role of tissue fluid in the body?

  It surrounds cells and facilitates exchanges
• What is lymph?

  Tissue fluid that drains into lymphatic vessels
• What happens to lymph as it passes through lymph nodes?

  It gains white cells and antibodies
• What is the structure of a red blood cell?

  Biconcave disc shape with no organelles
• Why do red blood cells have a biconcave shape?

  To provide a large surface area for diffusion
• What allows red blood cells to change shape?

  Elastic membrane enables shape change
• What is the function of phagocytes (neutrophils)?

  Engulf and digest bacteria
• Why do neutrophils have a lobed nucleus?

  To help squeeze through capillary gaps
• What is the role of lymphocytes in the immune system?

  Some develop into plasma cells for antibodies
• What are the differences between blood, tissue fluid, and lymph?

  • Blood: Contains red and white cells, plasma proteins
  • Tissue Fluid: Few proteins, surrounds cells
  • Lymph: Contains some fats, few proteins
• What is pressure filtration in the context of capillaries?

  It forces small molecules through capillary walls
• What happens to water in capillaries after pressure filtration?

  Much returns to blood by osmosis
• What is oedema?

  Excess fluid accumulation in tissues
• What do lymphatic vessels do with excess fluid?

  Return it to the blood circulation
• Where are red and white blood cells produced?

  In stem cells in bone marrow
• How do lymphocytes circulate in the body?

  They enter blood from lymph nodes
• What is tidal volume?

  Volume of air breathed in one breath
• What is vital capacity?

  Maximum volume of air exhaled after a deep breath
• How does exercise affect tidal volume?

  Tidal volume increases after exercise
• What is the function of arteries?

  Transport blood from the heart
• What is the function of capillaries?

  Exchange of substances between blood and tissues
• What is the function of veins?

  Transport blood to the heart
• Why do veins have valves?

  To prevent backflow of blood
• What is the heart's role in the circulatory system?

  It pumps blood throughout the body
• What causes blood pressure in the circulatory system?

  Heart contractions push blood through vessels
• What is the significance of the heart's electrical activity?

  It helps diagnose heart conditions
• How do substances exchange between tissue fluid and cells?

  By diffusion, facilitated diffusion, and active transport
• What is the role of squamous epithelial cells in capillaries?

  They provide a short diffusion pathway
• What happens to water potential at the ends of a capillary?

  Water potential decreases at one end
• What is the relationship between pressure and water movement in capillaries?

  High pressure causes water to leave capillaries
• What is the significance of the chromosome number during cell division?

  It halves from diploid to haploid
• How do tissues, organs, and systems relate to each other?

  Tissues form organs, which make systems
• How do muscle cells rely on red blood cells?

  Red blood cells deliver oxygen to muscle cells