Examples

• blood vessel network is a route for blood to flow around the body
• I’m humans ( double circulation ) blood passes through the heart twice before it does one complete circuit in the body
• systematic circulation — carries oxygenated blood from the left ventricle to the body — deoxygenated blood returns to the right atrium of the body
• Pulmonary circulation - transports deoxygenated blood from the right ventricle to the lungs and oxygenated blood from the lungs to the left atrium
• Vertebrates have a closed circulation — although substances diffuse from the blood to the cells - blood remains enclosed in vessels
• Fish have a single circulation system - heart pumps deoxygenated blood to gills to pick up oxygen - goes to rest of the body - deoxygenated blood returns through the heart to be sent to gills again - single loop
• Insects - open circulation system

  • blood flows freely in body cavity - isn’t enclosed in vessels
  • heart contracts in wave - pumping haemolymph into a single main artery - opens into body cavity to flow around organs and returns to heart via valves