List the muscles involved in respiration and briefly describe their function.
Most candidates correctly identified the diaphragm, intercostals, abdominals and accessory
muscles as important. However, the majority of candidates omitted to mention the muscles of the
larynx, pharynx and airway and thus failed to achieve a good score. Good answers included a
detailed description of their function including differentiating between external and internal
intercostals.
Syllabus: B1b,1, 2a
References: Nunn’s respiratory physiology P76 – 80 and West, Respiratory Physiology: the
Essentials, pgs 93 - 95
As one only has a few minutes to come up with a coherent answer to this SAQ under exam conditions, this is probably the wrong scenario for a longform prose answer discussing the relations innervation and blood supply of every single muscle. It would probably be best to group them anatomically and present their function in a table.
Muscle group | Inspiratory function | Expiratory function |
Pharyngeal muscles
|
|
|
Laryngeal muscles |
|
|
Chest wall muscles
|
|
|
Diaphragm |
|
|
Abdominal muscles
|
|
|
Accessory muscles
|
|
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