Regulating breathing mechanisms

• What does the respiratory control centre (RCC) contain?

  Two centres: the inspiratory centre (IC) and the expiratory centre (EC)
• What is the role of the inspiratory centre (IC)?

  The IC controls the process of inspiration
• Which nerve stimulates the external intercostals during inspiration at rest?

  The intercostal nerve
• Which nerve stimulates the diaphragm during inspiration at rest?

  The phrenic nerve
• How does inspiration during exercise differ from inspiration at rest?

  During exercise, the diaphragm is stimulated more by the phrenic nerve, leading to stronger muscle contractions
• What additional inspiratory muscles are stimulated during exercise?

  Pectoralis minor and sternocleidomastoid
• What happens during expiration at rest after approximately 2 seconds of inspiration?


  The IC stops stimulation of the phrenic and intercostal nerves, allowing the diaphragm and external intercostals to relax
• How does expiration occur at rest?

  Expiration happens passively due to the natural recoil of the lungs
• What is the role of the expiratory centre (EC) during exercise?

  The EC controls expiration by stimulating muscles to contract
• Which muscles does the expiratory centre stimulate during exercise?


  Internal intercostals and rectus abdominus
• What do chemoreceptors detect during exercise?

  Chemoreceptors detect an increase in carbon dioxide (CO2) and a decrease in oxygen (O2)
• How do proprioceptors contribute to respiratory regulation during exercise?

  Proprioceptors stimulate additional inspiratory muscles, increasing the force of contraction and depth of breathing
• What do thermoreceptors detect during exercise?

  Thermoreceptors detect increased blood temperature
• What do baroreceptors detect during exercise?

  Baroreceptors detect an increase in lung inflation
• What is the Hering-Breuer reflex?


  The Hering-Breuer reflex prevents lungs from overinflating
• What is the role of the internal intercostals during forced expiration?

  They are stimulated to contract to cause forced expiration during exercise
• What is the role of the rectus abdominus during forced expiration?

  It is stimulated to contract to assist in forced expiration during exercise
• What is meant by "chemical control" in respiratory regulation?


  Chemical control refers to the role of chemoreceptors and the changes they cause in respiratory function