Circulation

You should know about:

  1. the composition and functions of blood including:
  2. red blood cells, white blood cells and plasma;
  3. the structure and functions of blood vessels including:
  4. arteries, veins, portal veins, and capillaries;
  5. blood groups;
  6. and you should know about the heart.

The page about my heartbeat is just a bit of fun.