9.1 Circulatory system

• The circulatory system as a system of blood vessels with a pump and valves to ensure one-way flow of blood.
• • Single Circulation System (fish):
  • Blood flows through the heart once every complete circuit (No Septum)
  • Two heart chambers (Atrium and Ventricle)
  • Blood absorbs oxygen in the gills in lower-pressure
  • Released in body cells, then back to the heart

  
• • Double Circulation System:
  • Four heart chambers
  • Blood passes through the heart twice every complete circuit
  • Oxygenated in the lungs, to the heart, to the body, and back to the heart.

  
• Advantages of double circulation system: delivers greater blood flow rate to tissues around the body as the heart pumps the rich oxygenated blood to it from the lungs, preventing the mixing of oxygenated and deoxygenated blood.