Cardiovascular

• What is the function of the heart valves?

  To stop blood from flowing in the wrong direction
• What are the four main chambers of the heart?

  Right atrium, left atrium, left ventricle, right ventricle
• What are the names of the valves mentioned in the video?

  biscupid valve (left) and tricuspid valve (right)
• Where does blood enter the heart from the deoxygenated side?

  Through the superior vena cava
• Where does blood leave the heart from the left ventricle?

  Out of the aorta to the rest of the body
• What is the role of the sinoatrial (SA) node?

  It is the pacemaker of the heart responsible for causing the heart to beat
• What happens when the SA node sends out electrical signals?

  It stimulates both atria to contract and pushes blood into the ventricles
• What is the function of the atrioventricular (AV) node?

  To send an electrical impulse to make the ventricles contract
• What are Purkinje fibers responsible for?

  They conduct electrical impulses to stimulate the outer walls of the ventricles
• What is atrial systole?

  The contraction phase of the atria
• What is the term for the relaxation phase of the atria?

  Atrial diastole
• What is the term for the phase when the heart is contracting?

  Systole
• What is ventricular systole?

  The contraction phase of the ventricles
• What is the term for the relaxation phase of the ventricles?

  Ventricular diastole
• How does blood flow through the heart?

  1. Blood enters through the superior vena cava (deoxygenated)
  2. Atria contract (atrial systole)
  3. Blood flows into ventricles
  4. Ventricles contract (ventricular systole)
  5. Blood leaves through the aorta (oxygenated) or pulmonary artery (to lungs)
• What does it mean that the heart is myogenic?

  It generates its own impulses
• How does the SA node behave during rest or exercise?

  It continues to fire regardless of the state
• What can stimulate an increased heart rate?

  Chemical changes and impulses
• What is the bundle of His?


  A group of specialized heart muscle cells that transmit electrical signals from the atrioventricular node to the ventricles.
• What are the purkinje fibres?


  Muscles fibres that conduct impulses in the walls of the ventricles
• mnemonic the memorise conduction system?

  SAN

  Atrial systole

  AVN

  Purkinje fibres

  Ventricular systole

  (Sally always aims balls past Vicky)
• What are chemoreceptors?


  Detect chemicals changed such as an increase in carbon dioxide—>increase HR
• what are baroreceptors?


  detect changes in blood pressure—>decrease HR
• what are proprioceptors ?


  Sensory receptors in muscles and tendons, that detect changes in muscle movement—>increase HR
• Equation for cardiac output 


  Cardiac output (Q)= Stroke volume (SV) X HR
• What is cardiac hypertrophy? 


  the thickening of muscular wall of the heart so it becomes bigger and stronger so larger ventricular cavity.
• what is bradycardia? 


  a decrease in resting heart rate below 60 beats per minute
• How is maximal heart rate calculated?

  Maximal heart rate is calculated as 220 minus your age.
• What does resting heart rate refer to?

  Resting heart rate refers to the heart rate at rest.
• What factors can affect resting heart rate?

  Factors include fitness, exercise, stress, anxiety, temperature, body position, and medication intake.
• How does heart rate change during exercise?

  During exercise, the heart rate increases proportionally to the intensity of the exercise.
• What happens to heart rate after exercise stops?

  The heart rate begins to decrease as soon as exercise stops.
• What influences the time it takes for heart rate to return to resting levels?

  The time it takes for heart rate to return to resting levels is dependent on fitness levels.
• What can cause variations in heart rate outside of exercise?

  Variations can be caused by nervous excitement, fear, cold, or physical illness.
• What is heart disease commonly referred to as?

  Heart disease is commonly referred to as coronary heart disease or CHD.
• What causes coronary heart disease?

  Coronary heart disease is caused by a build-up of cholesterol and fatty substances that narrow the arteries.
• What is angina?

  Angina is chest pain caused by a decrease in oxygen supply to the heart muscle.
• What happens during a heart attack?

  A heart attack occurs when there is a complete cut-off of blood supply to a part of the heart.
• How does regular exercise affect the heart muscle?

  Regular exercise strengthens the heart muscle and improves its ability to pump blood efficiently.
• What does the American Heart Association recommend for aerobic activity?

  The American Heart Association recommends at least 150 minutes per week of moderate-intensity aerobic activity.