other

• why is it essential that heart rate can be changed?

  • uncontrolled can cause high pressure which can cause damage to capillaries and organs
  • exercise - needs to be higher so you can get more oxygen
  • sleep - lower rate to not waste energy
• what is an accelerator nerve?

  • a part of the sympathetic NS and delivers a higher than usual frequency of impulses to the sinoatrial node to increase the heart rate
• what is a vagus nerve?

  • opposite to accelerator nerve, part of parasympathetic NS and works to decrease heart rate by delivering a lower than usual frequency of impulses to the sinoatrial node
• what is a chemoreceptor?

  • detect chemical changes, e.g. oxygen concentration, carbon dioxide levels, pH of blood
• what is a baroreceptor?

  • detects changes in blood pressure
• what is the carotid artery?

  • primary vessels supplying blood to brain and face
• where are chemoreceptors found?

  • aorta
  • carotid artery
  • medulla
• what occurs when there is a lowered pH?

  • high CO2 concentration, carbonic acid is formed when CO2 interacts with water in the blood
  • chemoreceptors detect this and trigger increased heart rate
  • blood flows quickly to lungs so CO2 can be exhaled
• where are baroreceptors located?

  • aorta
  • vena cava
  • carotid arteries