Heart and blood vessels

• Functions of transport:

  oxygen

  carbon dioxide

  digestive food

  hormones

  waste products - urea
• Chambers of the heart.

  our system has a double circulatory system because red blood cells go around twice.

  
• Right atrium -> right ventricle -> lungs -> left atrium -> left ventricle

  -> body cells
• Arteries:

  • under high blood pressure

  • have thick muscular and elastic walls

  • has small lumen (the hole in vessel)

  • carry oxygenated (red) blood away from the heart to the body
• veins:

  • under low blood pressure

  • have thin walls

  •small lumen

  • carry deoxygenated (blue) blood to the heart from the body
• Capillaries:

  • thin walls

  •one cell thick

  • substances are able to pass in and out as blood and cells

  • grow narrow vessels running through body