Open & closed circulation systems

• What is an open circulatory system?

  -instead of blood, there is haemolymph

  -haemolymph is found in the haemocoel/body cavity

  -haemolymph bathes all cells and organs

  -many animals have a heart that pumps haemolymph from one area of the haemocoel to another
• How is oxygen delivered in a open circulatory system?

  Delivered directly to tissues by the tracheae
• What are the advantages of an open circulatory system?

  -requires less energy

  -better regulation for body temperature
• What are the disadvantages of an open circulatory system?

  -it is not feasible in larger animals
• What types of organism have an open circulatory system?

  Arthropods
• What is a closed circulatory system?

  -blood travels in blood vessels

  -impetus is generated by a muscular pump/heart
• What are the advantages of a closed circulatory system?

  -delivers blood quickly to tissues under pressure

  -creates a larger amount of pressure, allowing blood to travel further distances

  -red blood cells contain haemoglobin which transports oxygen

  -rapidity of transport has enabled evolution of larger size in animals
• What are the disadvantages of closed circulation?

  -requires more energy
• What types of organism have a closed circulatory system?

  Earthworms, fish, mammals