The blood vessels

• Arteries carry blood ___________ the heart.

  away from

  Remember 'A for Artery' and 'A for Away from the heart'. 
• Capillaries carry blood through the body tissues, allowing oxygen, nutrients, and waste products, to be exchanged between tissues and the blood.
• Veins carry blood ___________ the heart.

  towards
• 1. Arteries are large and carry blood at a very high pressure.
  2. Artery walls have a thick middle layer, containing both muscle and elastic tissue.
  3. The muscle tissue provides strength, and allows the arteries to direct blood flow.
  4. The elastic tissue allows the arteries to stretch and recoil.
  5. Compared to their walls, arteries have a relatively narrow lumen, which keeps the blood pressure high.
• 1. Capillaries are the smallest of the three blood vessels.
  2. The role of capillaries is to exchange nutrients and waste products with the tissues.
  3. Capillary walls are permeable, meaning substances are able to move through them.
  4. Their walls are also only one cell thick which means a short distance for diffusion.
  5. Capillaries carry blood at a low pressure and have a lower rate of flow than arteries.


  Structure and function of capillaries 
• Which of the following substances are nutrients that are exchanged between the blood in the capillaries and the body tissues?

  Urea

  Glucose

  Carbon dioxide

  Amino acids

  Proteins 

  Glucose + Amino Acids
• Which of the following substances are waste products that are exchanged between the blood in the capillaries, and the body tissues?

  Carbon dioxide

  Urea

  Glucose

  Amino acids

  Oxygen

  Proteins 

  Carbon Dioxide + Urea
• • The role of veins is to carry blood from the body (or lungs) back to the heart.
  • Veins are a similar size to arteries, but they have relatively thin walls and a relatively wide lumen
  • This is because they carry blood at a much lower pressure.
  • Veins also contain valves to prevent the blood from flowing backwards.


  Structure and function of veins 
• Which of the following substances are exchanged between the blood in the capillaries, and the body tissues?

  Carbon dioxide

  Glucose

  Proteins 

  Urea

  Oxygen

  Carbon dioxide, Glucose, Urea, Oxygen
• Artery


  What is X? (Capillary, Vein or Artery)

  
• Arteries are large vessels like veins. The key difference is that arteries have relatively thicker walls and a smaller lumen compared to veins. 
• Rate = Volume / Time
• If you consider all the blood vessels inside of a human body, which type of blood vessel accounts for the majority of the cross-sectional area?

  Arteries 

  Capillaries 

  Veins

  Capillaries 
• heart -> arteries -> capillaries -> veins -> heart