Circulatory System

• Vertebrates have a closed circulatory system
• Lymphatic system - open system, carries lymph to heart, leukocyte production
• Larger animals = higher blood pressure
• lamprey/hagfish

  • Single circulation (heart, gills, capillaries)
• Chondrichthyes

  • Single circulation
  • Counter-clockwise rotation during development
• Actinopterygii

  • Single circulation
• Amphibians

  • More aortic arches like fish-sharks in gills
  • Double circulation
• Reptiles

  • No thermoregulation (cold-blooded)
  • Double circulation
• Mammals 

  • Thermoregulation through carotid rate or dilation/constriction of vessels
• Circulatory system functions

  • Transports O2 and nutrients, nitrogenous waste
  • Shortens diffusion distance
  • Distributes heat
  • Hormone transport
• Features

  • Circulatory fluid
  • Set of tubes 
  • Muscular pump