Cardiovascular system

• What is the pulmonary circuit ?

  Carries blood for the heat to the lungs
• What is the systematic circuit ?

  Carries blood from the heart to the body
• What is the conduction system ?

  Five structures that pass the electrical impulse through the cardiac muscle
• What is myogenic ?

  The heart generates it own electrical impulse
• What is the SA node ?

  Generates electrical impulses
• What is the AV node ?

  Collects and delays the impulse
• What is the bundle of his ?

  Feed the impulse from the atria into the ventricles
• What is the bundle branches ?

  Slips the impulse in two
• What is the purkyne fibres ?

  Cause ventricles to contract
• What is diastole ?

  Relaxation phase of the heart
• What is systole ?

  The contraction phase of the heart
• What is stroke volume ?

  the amount of blood ejected by the heart in any one contraction
• What is heart rate?

  number of beats per minute
• What is cardiac output ?

  the amount of blood pumped by the heart per minute
• What is starling law ?

  An increased Venus return will increase stroke volume due to a greater stretch on ventricular walls
• Why does cardiac output a d stoke volume plateau?

  The plateau at higher intensities due to the heart rate limiting the amount of filling time
• Stage on in heart response to exercise ?

  Anticipatory rise in the heart rate due to adrenaline
• Stage two of heart rate response to exercise ?

  Rapid increase in HR to meet the oxygen demand
• Stage three of heart rate response to exercise ?


  Trained plateau as oxygen supply meets oxygen
• Stage four of heart rate response to exercise ?

  Untrained HR and plateau later
• Stage five of heart rate response to exercise ?

  HR rapidly decreases in recovery
• Stage six of heart rate response to exercise ?

  HR slowly decreases but above resting HR
• What is the heart rate controlled by ?

  By the autonomic nervous system
• Where is the cardiac control centre (CCC) located ?

  Medulla oblongta
• What are the three neural controls ?

  Chemoreceptors

  Proprorecptors

  Baroreceptors
• What does the chemoreceptors do ?

  Detect change in chemicals
• What does the propriorectors do ?

  Detect movement
• What does the baroreceptors ?

  Detects change In blood pressure
• What are the two intrinsic controls ?

  Temperature

  Venous return
• What is temperature do ?

  Changes blood viscosity and speed of nerve impulse
• What does venous return do ?

  Increase stretch on ventricles resulting in an increase in stoke volume
• What is the hormonal control ?

  Adrenaline and noradrenaline
• What does Adrenaline and noradrenaline do ?

  Increases force of contraction on ventricles and speed of nerve impulse
• what is venous return ?

  the amount f blood that flows back to the atria
• what are the venous return mechanisms ?

  gravity

  pocket valve

  skeletal muscle pump

  respiratory pump

  smooth muscle
• what is blood pooling ?

  when blood accumulates in the extremedies
• what might happen as a result of blood pooling ?

  light headed

  fainting
• how does an active cool down help reduce blood pooling ?

  it maintains venous return by keeping the skeletal muscle pump and respiratory pump active
• What is the vascular shunt mechanism ?

  Control the redistribution of blood around the whole body
• how is blood redistributed ?

  by the sympathetic control of the arterioles and the pre-capillary sphincter