Circulatory system

• Vein


  Blood vessel that carries blood towards the heart
• Artery


  Blood vessel that carries blood away from the heart
• Capillaries


  Tiny blood vessels where exchange of oxygen, nutrients and waste products occurs between blood and tissues
• Blood pathway


  1. Right atrium

  2. Right ventricle

  3. Lungs

  4. Pulmonary artery

  5. Pulmonary veins

  6. Left atrium

  7. Left ventricle

  8. Aorta
• Function of valves


  • Prevent backflow
• Varicose vein


  Enlarged, swollen and twisted veins often blue or dark purple, caused by weak or damaged valves and increased pressure in the vein
• Diastolic


  Heart contracts
• Systolic


  Heart relaxes
• How blood pressure is measured

  Using a cuff and a gauge, measures diastolic pressure
• Causes of change in blood pressure

  Stress, diet, exercise
• Heart attack is blocked blood flow to the heart
• Stroke is blocked blood flow to the brain
• To prevent heart disease: healthy diet, exercise, stress management
• Blood types


  • A+
  • A-
  • B+
  • B-
  • AB+
  • AB-
  • O+
  • O-
• Golden blood


  Rh- (lacks all Rh antigens), can donate to everyone
• Human body contains 4-6 litres of blood
• Fibrinogen


  Protein responsible for blood clotting
• Main functions of lymphatic system

  • Support immune system
  • Maintain fluid balance
• Lymph nodes filter lymph fluid, trapping and destroying pathogens and abnormal cells, helping to fight infection and disease
• Left ventricle contains more muscle to force blood to all parts of the body
• Systemic circulation


  Largest pathway - entire cardiovascular system
• Purpose of hemoglobin


  • Transport oxygen from lungs to tissues of the body
  • Carry CO2 from tissues back to the lungs for exhalation
• Iron is essential for the production and transport of oxygen
• Decrease in oxygen transport due to low iron

  Fatigue, weakness, low energy
• Blood components


  • Red blood cells (erythrocytes)
  • White blood cells (leukocytes)
  • Platelets (thrombocytes)
  • Plasma
• Red blood cells


  • Transport oxygen from lungs to body 40-45%, in bone marrow, 120 days
  • Disk-shaped
• White blood cells


  • Protect body against infections and foreign particles
  • Involved in inflammation, allergic reactions and immune response, don’t contain hemglobin, in bone marrow 1%
• Platelets


  • Responsible for blood clotting, 1%, form plug to seal wound
• Plasma


  • 80% water, 10% salts, nutrients and plasma proteins (albumins, globulins, fibrinogen)
  • Transports nutrients, hormones, vitamins
  • Regulates osmotic pressure and blood volume
  • Maintains pH balance, 55%, carry waste to kidney, liver,lung
• The heart has four chambers - two atria and two ventricles.
• Atria are the upper chambers that receive blood from veins.
• Ventricles are the lower chambers that pump blood out to arteries.
• Valves prevent backflow of blood between chambers or into the wrong direction through vessels.
• Valves prevent backflow of blood during contractions.
• Blood flows through one-way valves between the atria and ventricles.
• Heart rate is controlled by the sinoatrial node (SA node), which generates electrical impulses to coordinate contraction of cardiac muscle fibers.
• Blood flows one way only through the circulatory system due to valves.
• Electrical impulse travels along the atrioventricular bundle (AV bundle) and branches to stimulate contraction of the ventricles.
• Blood flows from right atrium to left atrium via pulmonary circulation.
• Systemic circulation is the flow of oxygenated blood from the left side of the heart to all other parts of the body except the lungs.