Circulatory system

• Humans have a double circulatory system, meaning blood passes through the heart 2 times in 1 circulation.
• The human circulatory systems features

  • Heart
  • Blood vessels
  • Blood
• Why are we double circulatory?

  • Blood can be pumped out at higher pressures, therefore increasing the rate of blood flow = more Oxygen can be delivered to the cells
• Heart

  • Deoxygenated blood flows through the Vena Cava into the Right Atrium, before passing the Tricuspid Valve into the Right Ventricle
  • The Right Ventricle pushes it up through the Pulmonary Artery and to the lungs
  • Oxygenated blood returns through the Pulmonary Vein
  • This is pumped through the Left Atrium down through the Bicuspid valve to the Left Ventricle, up through the Aorta off to the body

  
• Heart - deoxygenated blood

  • Vena Cava
  • Right Atrium
  • Tricuspid valve
  • Right Ventricle
  • Pulmonary Artery
  • Lungs
• Heart - oxygenated blood

  • Pulmonary veIN
  • Left atrium
  • Bicuspid valve
  • Left ventricle
  • Aorta
  • Body
• Memorise the Heart

  • veIN = blood IN
  • Tri before you Bi (Tricuspid before Bicuspid)
• Blood vessels

  Vein

  • Big lumen
  • Thick wall (Oxygenated blood = higher pressure)
  • Valves = prevent backflow

  Capillaries

  • Very thin wall (One cell thick)
  • Permeable walls = Aids diffusion

  Artery

  • Small lumen
  • Thick wall (Blood is pumped out at high pressures)