Circulatory system

• Vena cava - carries deoxygenated blood from the body to the heart
• Pulmonary artery - carries deoxygenated blood from the heart to the lungs
• Aorta - carries blood from the heart to the body
• Pulmonary vein - carries oxygenated blood from the lungs to the heart
• Veins - carry blood to the heart

  • low pressure
  • large lumen
  • think walls
  • valves to prevent back flow
• adaptations of red blood cells

  • bioconcave disc shape (increase surface area)
  • no nucleus (more space for heamoglobin)
• Function of red blood cells

  • carry oxygen around the body for respiration
  • heamoglobin binds to oxygen
• Function of white blood cells

  • fights against infection
  • lymphocytes - produce antibodies (binds to pathogens’ antigens) and antitoxins (neutralises toxins produced by pathogen)
  • phagocytes - phagocytosis: engulfs and ingests the pathogen to destroy it
• Function of platelets

  • Small fragments of red blood cells
  • repair damaged tissue by clotting blood
• function of plasma: carries everything around the body including…

  • waste products (urea and CO2)
  • amino acids
  • protiens
  • hormones
• What causes coronary heart diseases?

  • layers of fatty material build up on coronary arteries reducing blood flow and oxygen to heart and bodies
• statins?

  • drugs to reduce cholesterol levels to treat coronary heart disease
• Stents?

  • mesh wire tube inserted i to artery to open it up to improve blood flow for someone with coronary heart disease
• What causes cardiovascular diseases

  • Faulty valves reducing blood flow
• Treatments for cardiovascular disease:

  • Mechanical or biological valves
  • donor or artificial heart
• Risks of surgeries for cardiovascular disease

  • chance if rejection
  • blood clots
  • side effects