·˚ ༘ blood vessels ·˚ ༘

• What do the arteries do?


  Transport oxygenated blood from the heart to the rest of the body. (High pressure!)
• What do the veins do?


  Transport blood from organs to the heart.
• What do the capillaries do?


  Join arteries and veins through organs.
• What is the structure of an artery?

  thick walls with elastic and muscle fibres & a small lumen.
• State the structure of veins.

  Low pressure and no pulse so the walls are thin and the lumen is large.
• State the structure of capillaries.


  These are lots of tiny vessels that go through all of the organs in you body. This gives a very large surface area to increase the rate of diffusion of substances between the capillaries and the cells in the organs
• What are the advantages of the double circulatory system?

  the pressure of the oxygenated blood coming from the lungs is increased again before being sent out to the rest of the body.

  This makes the system very efficient because more areas of our body can receive fully oxygenated blood quickly.