Blood vessels

• Hydrogen bonds


  Property of water that allows molecules to stick together and flow
• Types of blood vessels

  • Arteries
  • Veins
  • Capillaries
• Role of each blood vessel

  1. Arteries - Carry oxygenated blood (to respiring tissues)

  2. Veins - Carry deoxygenated blood (to the heart)

  3. Capillaries - Site of diffusion in lungs/at respiring tissues
• Veins


  • Extra structure - Valves

  Purpose - To prevent backflow of blood
• Endothelium


  Layer of cells lining the interior surface of blood vessels
• Lumen


  The inside open space or channel within a blood vessel
• Elastic fibres


  Structural component of blood vessel walls
• Collagen


  Structural component of blood vessel walls
• Veins are not actually 'round/circular' they tend to be flattened. This is due to the lower volume of collagen fibres, muscle and elastic tissue in their walls.
• Why do veins have less muscle, elastic tissue and collagen?

  Because they have lower blood pressure compared to arteries
• Sequence of heart chambers, valves and blood vessels a drop of blood would pass through

  1. Right atrium

  2. Atrioventricular/tricuspid valve

  3. Right ventricle

  4. Pulmonary artery

  5. Pulmonary vein

  6. Left atrium

  7. Atrioventricular/bicuspid valve

  8. Left ventricle

  9. Aorta